ASUS P4BLS User Manual

P4B-LS

®

User Guide

Motherboard

Checklist

E861
First Edition October 2001

Copyright © 2001 ASUSTeK COMPUTER INC. All Rights Reserved.

No part of this manual, including the products and software described in it, may be
reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any
language in any form or by any means, except documentation kept by the purchaser for
backup purposes, without the express written permission of ASUSTeK COMPUTER INC.
(“ASUS”).

Product warranty or service will not be extended if: (1) the product is repaired, modified or
altered, unless such repair, modification of alteration is authorized in writing by ASUS; or (2)
the serial number of the product is defaced or missing.

ASUS PROVIDES THIS MANUAL “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES
OR CONDITIONS OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
IN NO EVENT SHALL ASUS, ITS DIRECTORS, OFFICERS, EMPLOYEES OR AGENTS BE
LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
(INCLUDING DAMAGES FOR LOSS OF PROFITS, LOSS OF BUSINESS, LOSS OF USE
OR DATA, INTERRUPTION OF BUSINESS AND THE LIKE), EVEN IF ASUS HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES ARISING FROM ANY DEFECT OR
ERROR IN THIS MANUAL OR PRODUCT.

SPECIFICATIONS AND INFORMATION CONTAINED IN THIS MANUAL ARE FURNISHED
FOR INFORMATIONAL USE ONLY, AND ARE SUBJECT TO CHANGE AT ANY TIME
WITHOUT NOTICE, AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY ASUS.
ASUS ASSUMES NO RESPONSIBILITY OR LIABILITY FOR ANY ERRORS OR
INACCURACIES THAT MAY APPEAR IN THIS MANUAL, INCLUDING THE PRODUCTS
AND SOFTWARE DESCRIBED IN IT.

Products and corporate names appearing in this manual may or may not be registered
trademarks or copyrights of their respective companies, and are used only for identification or
explanation and to the owners’ benefit, without intent to infringe.

ii

Contents

FCC/CDC statements .....................................................................vi

Safety information .......................................................................... vii

About this guide ............................................................................ viii

How this guide is organized.................................................. viii

Conventions used in this guide............................................... ix

Where to find more information .............................................. ix

ASUS contact information ................................................................x

Chapter 1: Product introduction ......................................... 1-1

1.1 Welcome!............................................................................ 1-1

1.2 Package contents ............................................................... 1-1

1.3 Special features .................................................................. 1-2

1.3.1 Product highlights ................................................... 1-2

1.3.2 Value-added solutions ............................................ 1-3

1.4 Major components .............................................................. 1-4

1.4.1 Identifying the motherboard components ................ 1-4

1.4.2 Pre-installed accessory........................................... 1-7

Chapter 2: Hardware information ........................................ 2-1

Features

2.1 Motherboard installation ...................................................... 2-1

2.1.1 Placement direction ................................................ 2-1

2.1.2 Screw holes............................................................ 2-1

2.2 Motherboard layout ............................................................. 2-2

2.3 Before you proceed............................................................. 2-3

2.4 Central Processing Unit (CPU) ............................................ 2-4

2.4.1 Overview ................................................................ 2-4

2.4.2 Installing the CPU ................................................... 2-5

2.4.3 Installing the heatsink and fan................................. 2-7

2.4.4 Connecting the CPU fan cable................................ 2-9

2.5 System memory ................................................................ 2-10

2.5.1 Overview .............................................................. 2-10

2.5.2 Memory configurations ......................................... 2-10

2.5.3 Installing a DIMM ...................................................2-11

2.5.4 Removing a DIMM................................................ 2-12

iii

Safeguards

Contents

2.6 Expansion slots................................................................. 2-13

2.6.1 Installing an expansion card.................................. 2-13

2.6.2 Configuring an expansion card ............................. 2-14

2.6.3 PCI slots and ASUS proprietary slot...................... 2-15

2.6.4 AGP slot ............................................................... 2-15

2.6.5 CNR slot............................................................... 2-16

2.7 Switches and jumpers ....................................................... 2-17

2.8 Connectors ....................................................................... 2-24

Chapter 3: Powering up ....................................................... 3-1

3.1 Starting up for the first time.................................................. 3-1

3.2 Vocal POST Messages ....................................................... 3-2

3.3 Powering off the computer................................................... 3-4

Chapter 4: BIOS setup ......................................................... 4-1

4.1 Managing and updating your BIOS...................................... 4-1

4.1.1 Using the computer system for the first time ........... 4-1

4.1.2 Updating BIOS procedures ..................................... 4-3

4.2 BIOS Setup program........................................................... 4-5

4.2.1 BIOS menu bar....................................................... 4-6

4.2.2 Legend bar ............................................................. 4-6

4.3 Main Menu .......................................................................... 4-8

4.3.1 Primary and Secondary Master/Slave ..................... 4-9

4.3.2 Keyboard Features ............................................... 4-13

4.4 Advanced Menu ................................................................ 4-15

4.4.1 Chip Configuration ................................................ 4-17

4.4.2 I/O Device Configuration....................................... 4-20

4.4.3 PCI Configuration ................................................. 4-22

4.5 Power Menu...................................................................... 4-24

4.5.1 Power Up Control ................................................. 4-26

4.5.2 Hardware Monitor ................................................. 4-28

4.6 Boot Menu ........................................................................ 4-29

iv

4.7 Exit Menu.......................................................................... 4-31

Contents

Chapter 5: Software support ............................................... 5-1

5.1 Install an operating system.................................................. 5-1

5.1.1 Windows 98 first time installation ............................ 5-1

5.2 Support CD information....................................................... 5-1

5.2.1 Running the support CD ......................................... 5-1

5.2.2 Main menu ............................................................. 5-2

5.2.3 Software menu ....................................................... 5-3

5.2.4 Drivers menu .......................................................... 5-5

5.2.5 DOS Utilities menu ................................................. 5-6

5.2.6 ASUS Contact Information...................................... 5-6

5.2.7 Other information .................................................... 5-7

5.3 Software information ........................................................... 5-9

5.3.1 ASUS Update ......................................................... 5-9

5.3.2 Winbond Voice Editor ............................................5-11

Glossary ................................................................................ G-1

Index ........................................................................................ I-1

v

FCC/CDC statements

Federal Communications Commission Statement

This device complies with FCC Rules Part 15. Operation is subject to the
following two conditions:

• This device may not cause harmful interference, and

• This device must accept any interference received including interference

that may cause undesired operation.

This equipment has been tested and found to comply with the limits for a
Class B digital device, pursuant to Part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference
in a residential installation. This equipment generates, uses and can radiate
radio frequency energy and, if not installed and used in accordance with
manufacturer’s instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not
occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment to an outlet on a circuit different from that to

which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

The use of shielded cables for connection of the monitor to the
graphics card is required to assure compliance with FCC regulations.
Changes or modifications to this unit not expressly approved by the
party responsible for compliance could void the user’s authority to
operate this equipment.

Canadian Department of Communications Statement

This digital apparatus does not exceed the Class B limits for radio noise
emissions from digital apparatus set out in the Radio Interference
Regulations of the Canadian Department of Communications.

This class B digital apparatus complies with Canadian ICES-003.

vi

Safety information

Electrical safety

• To prevent electrical shock hazard, disconnect the power cable from
the electrical outlet before relocating the system.

• When adding or removing devices to or from the system, ensure that
the power cables for the devices are unplugged before the signal
cables are connected. If possible, disconnect all power cables from the
existing system before you add a device.

• Before connecting or removing signal cables from the motherboard,
ensure that all power cables are unplugged.

• Seek professional assistance before using an adpater or extension
cord. These devices could interrupt the grounding circuit.

• Make sure that your power supply is set to the correct voltage in your
area. If you are not sure about the voltage of the electrical outlet you
are using, contact your local power company.

• If the power supply is broken, do not try to fix it by yourself. Contact a
qualified service technician or your retailer.

Operation safety

• Before installing the motherboard and adding devices on it, carefully
read all the manuals that came with the package.

• Before using the product, make sure all cables are correctly connected
and the power cables are not damaged. If you detect any damage,
contact your dealer immediately.

• To avoid short circuits, keep paper clips, screws, and staples away from
connectors, slots, sockets and circuitry.

• Avoid dust, humidity, and temperature extremes. Do not place the
product in any area where it may become wet.

• Place the product on a stable surface.

• If you encounter technical problems with the product, contact a

qualified service technician or your retailer.

vii

About this guide

This user guide contains the information you need when installing the
ASUS P4B-LS motherboard.

How this guide is organized

This manual contains the following parts:

• Chapter 1: Product introduction

This chapter describes the features of the P4B-LS motherboard. It
includes brief descriptions of the special attributes of the motherboard
and the new technology it supports.

• Chapter 2: Hardware information

This chapter lists the hardware setup procedures that you have to
perform when installing system components. It includes description of
the switches, jumpers, and connectors on the motherboard.

• Chapter 3: Powering up

This chapter describes the power up sequence and gives information
on the BIOS beep codes.

• Chapter 4: BIOS setup

This chapter tells how to change system settings through the BIOS
Setup menus. Detailed descriptions of the BIOS parameters are also
provided.

• Chapter 5: Software support

This chapter describes the contents of the support CD that comes with
the motherboard package.

• Glossary

This part lists the technical terms that you may encounter when
reading this document.

• Index

This part contains an alphabetical list of the topics found in this
document.

viii

Conventions used in this guide

To make sure that you perform certain tasks properly, take note of the
following symbols used throughout this manual.

WARNING: Information to prevent injury to yourself when trying
to complete a task.

CAUTION: Information to prevent damage to the components
when trying to complete a task.

IMPORTANT: Information that you MUST follow to complete a
task.

NOTE: Tips and additional information to aid in completing a task.

Where to find more information

Refer to the following sources for additional information and for product
and software updates.

1. ASUS Websites
The ASUS websites worldwide provide updated information on ASUS

hardware and software products. The ASUS websites are listed in the
ASUS Contact Information on page x.

2. Optional Documentation

Your product package may include optional documentation, such as
warranty flyers, that may have been added by your dealer. These
documents are not part of the standard package.

ix

ASUS contact information

ASUSTeK COMPUTER INC. (Asia-Pacific)

Address: 150 Li-Te Road, Peitou, Taipei, Taiwan 112
General Tel: [phone]
General Fax: [phone]
General Email: [e-mail]

Technical Support

MB/Others (Tel): [phone] (English)
Notebook (Tel): [phone] (English)
Desktop/Server (Tel): [phone] (English)
Support Fax: [phone]
Support Email: [e-mail]
Web Site: www.asus.com.tw
Newsgroup: cscnews.asus.com.tw

ASUS COMPUTER INTERNATIONAL (America)

Address: 6737 Mowry Avenue, Mowry Business Center,

Building 2, Newark, CA 94560, USA
General Fax: [phone]
General Email: [e-mail]

Technical Support

Support Fax: [phone]
Notebook (Tel): 1-877-918-ASUS (2787)
Web Site: www.asus.com
Support Email: [e-mail]

ASUS COMPUTER GmbH (Europe)

Address: Harkortstr. 25, 40880 Ratingen, BRD, Germany
General Fax: [phone]
General Email: [e-mail] (for marketing requests only)

Technical Support

Support Hotline: MB/Others: [phone]
Notebook (Tel): [phone]
Support Fax: [phone]
Support (Email): www.asuscom.de/de/support (for online support)
Web Site: www.asuscom.de

x

Chapter 1

This chapter describes the features of the
P4B-LS motherboard. It includes brief
explanations of the special attributes of the
motherboard and the new technology it
supports.

Product introduction

ASUS P4B-LS motherboard

1.1 Welcome!

Thank you for buying the ASUS® P4B-LS motherboard!

The ASUS
technology making it another standout in the long line of ASUS quality
motherboards!

The P4B-LS incorporates the Intel
package/Northwood Processor coupled with the Intel
chipset to set a new benchmark for an effective desktop platform solution.

Supporting up to 3GB of system memory with PC100/133 unbuffered
SDRAM, high-resolution graphics via an AGP 4X slot, communication and
networking options through a CNR slot, high-speed data transfers using
the A T A100 protocol, AC ‘97-compliant audio features, and an ASUS
proprietary LAN/SCSI slot, the P4B-LS spells out power computing!

Before you start installing the motherboard, and hardware devices on it,
check the items in your package with the list below.

P4B-LS motherboard delivers a host of new features and latest

®

Pentium® 4 Processor in 478-pin

®

845 (Brookdale)

1.2 Package contents

Check your P4B-LS package for the following items.

ASUS P4B-LS motherboard (ATX form factor: 12-in x 8.6-in)
ASUS LS99 LAN/SCSI card (for ASUS LS99 proprietary expansion slot)
ASUS P4B-LS support CD
ASUS 2-port USB module
80-conductor ribbon cable for UltraDMA/33/66/100 IDE drives
40-conductor IDE cable
Ribbon cable for a 3.5-inch floppy drive
Bag of extra jumper caps
User guides
Quick Setup Guide and Reference Card

If any of the above items is damaged or missing, contact your retailer.

ASUS P4B-LS motherboard user guide

1-1

1.3 Special features

1.3.1 Product highlights

Latest processor technology

The P4B-LS motherboard supports the latest Intel Pentium 4 478/
Northwood Processor, also known as P4, via a 478-pin surface mount ZIF
socket. The Pentium 4 processor utilizes the advanced 0.18 micron
processor core in FC-PGA2 package for a 2.0GHz frequency, while the
Northwood processor uses the 0.13 micron processor core with 512KB L2
cache for up to a speedy 2.4+GHz frequency. The P4 offers optimized
performance for audio, video, and Internet applications. See section “2.4
Central Processing Unit (CPU)” on page 2-4 for more information.

ASUS POST Reporter™

P4B-LS offers a new exciting feature called the ASUS POST Reporter™ to
provide friendly voice messages and alerts during the Power-On Self-Tests
(POST). Through the system’s internal speaker, or an added external
speaker, you will hear the messages informing you of the system boot
status and causes of boot errors, if any. The bundled Winbond Voice
Editor software allows you to customize the voice messages, and provides
multi-language support. See section “5.3.2 Winbond Voice Editor” on page
5-11 for details.

ASUS EZ Plug™

This patented ASUS technology lets you use your existing power supply
rather than buying a new ATX 12V power supply. The ASUS EZ Plug™ is
a 4-pin auxillary +12V connector mounted on the motherboard that
connects a regular 4-pin device power connector from the power supply.
This connector is necessary to provide the additional power required by
the P4 CPU. Refer to page 1-5 and 2-28 for additional information.

Digital audio interface

On audio models, a digital audio connector is onboard to accommodate
the Sony-Philips Digital Interface (SPDIF) Out module, which supports
coaxial and optical interfaces. Experience 5.1-channel surround sound
and enhanced 3D audio while playing your favorite DVDs and computer
games. Turn to page 2-31 for details on this feature.

1-2

Chapter 1: Product introduction

LAN/SCSI interface

The ASUS proprietary expansion slot onboard supports the ASUS LS99
LAN/SCSI card. With this card installed, you can create a SCSI
configuration composed of up to 30 devices, including Ultra160 hard disk
drives, external storage subsystems, scanners, and CD-ROM drives. The
integrated 3Com 3C920 Fast Ethernet controller on the card supports a
32-bit PCI host interface thus providing a 10BASE-T/100BASE-TX
networking capability. Refer to the ASUS LS99 user’s manual for more
information.

1.3.2 Value-added solutions

Overclocking

The P4B-LS overclocking features:

• adjustable CPU frequency multiple in BIOS using the ASUS
JumperFree™ solution

• adjsutable FSB/MEM/PCI frequency ratio

• Stepless Frequency Selection (SFS) for fine-tuning system bus

frequency from 100MHz up to 200MHz at 1MHz increments

• optimized system performance through BIOS built-in Turbo Mode

• adjustable Vcore and VIO

ASUS iPanel support

The motherboard supports the ASUS iPanel to provide easy connectivity,
one-touch management of various peripherals, and convenient monitoring
of system status.

Special Card Reader support

The P4B-LS includes special connectors that support optional readers for
Smart Card, Secure Digital (SD) memory Card, and Memory Stick (MS).
The Smart Card Reader promotes cutting-edge technology featuring
increased security for authenticating online transactions, editing IC-based
information, and more. The SD/MS Reader allows portable high-capacity
storage through the sophisticated SD and MS devices.

Multi-language quick setup guide

The motherboard package includes a multi-language Quick Setup Guide
to let you set up your system the easiest way.

ASUS P4B-LS motherboard user guide

1-3

1.4 Major components

Before you install the P4B-LS motherboard, take some time to familiarize
yourself with its physical configuration and available features. This will
facilitate the motherboard installation and future upgrades. A sufficient
knowledge of the motherboard specifications will also help you avoid
mistakes that may damage the board and its components.

This section presents the motherboard components and points out their
specific locations. A brief description of each component follows. Refer to
Chapter 2 for detailed information on these components.

1.4.1 Identifying the motherboard components

30

29

28

27

1

26

20

19

5

6

7

8

9

10

11

12

13

14

15

16

17

18

4

3

2

25

24

23

22

21

Figure 1-1 Motherboard Components

Proceed to the succeeding pages for a brief description of each
component.

1-4

Chapter 1: Product introduction

1

CPU socket. A 478-pin surface mount, Zero Insertion Force (ZIF)

socket called mPGA478 B. This socket accommodates the Intel

®

Pentium® 4 478/Northwood Processor with 400MHz system bus.

2

North bridge controller. This controller called the Intel Memory

Controller Hub (MCH) is one of the two major components of the
Intel 845 (Brookdale) chipset. The MCH along with the south bridge
Intel I/O Controller Hub 2 (ICH2) are interconnected through the
Intel proprietary Hub interface. The MCH provides the processor
interface, system memory interface, AGP interface, and Hub
Interface.

3

SDRAM DIMM sockets. These three 168-pin DIMM sockets

support up to 3GB using unbuffered ECC or non-ECC PC100/133
SDRAM DIMMs.

4

ATX power connector. This 20-pin connector connects to an ATX

12V power supply. The power supply must have at least 1A on the
+5V standby lead (+5VSB).

5

Floppy disk connector. This connector accommodates the

provided ribbon cable for the floppy disk drive. One side of the
connector is slotted to prevent incorrect insertion of the floppy disk
cable.

6

ASUS EZ Plug™ Auxilliary +12V connector. This ASUS patented

auxilliary power connector is used if you don’t have an ATX +12V
power supply. Connect a 4-pin device connector from a standard
power supply to this connector to provide sufficient power to the
CPU.

7

IDE connectors. These dual-channel bus master IDE connectors

support up to four Ultra DMA/100/66, PIO Modes 3 & 4 IDE
devices. Both the primary (blue) and secondary (black) connectors
are slotted to prevent incorrect insertion of the IDE ribbon cable.

8

AGP slot. This Accelerated Graphics Port (AGP) slot supports 1.5V

AGP4X mode graphics cards for 3D graphical applications.

9

AGP warning LED. Serving as a smart burn-out protection for the

motherboard, this red LED lights up if you plug in any 3.3V AGP
card into the AGP slot. When this LED is lit, there is no way you
can turn on the system power even if you press the power button.
(The AGP LED feature is present on PCB R1.05 or later versions.)

ASUS P4B-LS motherboard user guide

1-5

10

South bridge controller. Referred to as the Intel I/O Controller

Hub 2 (ICH2) of the Intel 845 chipset, this controller provides the
I/O subsystem that allows access to the rest of the system. The
ICH2 integrates I/O functions such as system bus interface, Ultra
ATA/100, Low Pin Count (LPC) interface, Universal Serial Bus
(USB) 1.1 interface, PCI interface, and CNR interface.

11

12

13

14

15

16

DIP switches. This 10-switch Dual Inline Package (DIP) allows you

to set the CPU external frequency.
Speech controller. This Winbond speech controller supports

ASUS POST Reporter™ for configurable vocal POST alerts.
Flash EEPROM. This 2Mb firmware contains the programmable

BIOS program.
Super I/O chipset. This Low Pin Count (LPC) interface provides

the commonly used Super I/O functionality. The chipset supports a
high-performance floppy disk controller for a 360K/720K/1.44M/

2.88M floppy disk drive, a multi-mode parallel port, two standard
compatible UARTs, a Standard Infrared (SIR), one MPU-401 UART
mode compatible MIDI/game port, and a Flash ROM interface.

ASUS ASIC. This chip performs multiple system functions that
include hardware and system voltage monitoring, IRQ routing,
among others.

LAN/SCSI slot. This ASUS proprietary slot supports the ASUS
LS99 LAN/SCSI card that allows you to connect up to 30 SCSI
devices, and hook your PC to a network.

1-6

17

18

19

20

CNR slot. This slot is specifically designed for the Communications

and Networking Riser (CNR) card. The CNR supports V.90 analog
modem, six-channel audio, HPNA, USB Hub, and the 10BASE-T/
100BASE-TX Ethernet networking.

Onboard LED. This onboard LED lights up if there is a standby
power on the motherboard. This LED acts as a reminder to turn off
the system power before plugging or unplugging devices.

PCI slots. These five 32-bit PCI 2.2 expansion slots support bus
master PCI cards like SCSI or LAN cards with 133MB/s maximum
throughput.

Audio/Modem CODEC. This AC ’97 compliant audio CODEC
supports SPDIF Out feature.

Chapter 1: Product introduction

21

ATX 12V connector. This power connector connects the 4-pin 12V

plug from the ATX 12V power supply.

22
23

24

25

26

27

28

Microphone jack. This Mic (pink) jack connects a microphone.
Line In jack. This Line In (light blue) jack connects a tape player or

other audio sources.
Line Out jack. This Line Out (lime) jack connects a headphone or

a speaker.
Game/MIDI connector. This connector supports a joystick or a

game pad for playing games, and MIDI devices for playing or
editing audio files.

Serial ports. These two 9-pin COM1/COM2 ports are for pointing
devices or other serial devices.

Parallel port. This 25-pin port connects a parallel printer, a
scanner, or other devices.

USB ports. These two 4-pin Universal Serial Bus (USB) ports are
available for connecting USB devices such as a mouse and PDA.

29

PS/2 keyboard port. This purple 6-pin connector is for a PS/2

keyboard.

30

PS/2 mouse port. This green 6-pin connector is for a PS/2 mouse.

1.4.2 Pre-installed accessory

This motherboard is shipped with the heatsink retention module base
already installed. This module should fit the retention mechanism that
comes with a boxed CPU.

You do not have to remove the retention module base when installing
the CPU or installing other motherboard components.

Retention Module Base

Figure 1-2 Pre-installed Heatsink Retention Module Base

ASUS P4B-LS motherboard user guide

1-7

1-8

Chapter 1: Product introduction

Chapter 2

This chapter describes the hardware setup
procedures that you have to perform when
installing system components. It includes
details on the switches, jumpers, and
connectors on the motherboard.

Hardware information

ASUS P4B-LS motherboard

2.1 Motherboard installation

Before you install the motherboard, study the configuration of your chassis
to ensure that the motherboard fits into it. The P4B-LS uses the ATX form
factor that measures 12 inches x 8.6 inches, a standard fit for most
chassis.

Make sure to unplug the power cord before installing or removing the
motherboard. Failure to do so may cause you physical injury and
damage motherboard components.

2.1.1 Placement direction

When installing the motherboard, make sure that you place it into the
chassis in the correct orientation. The edge with external ports goes to the
rear part of the chassis. Refer to the image below.

2.1.2 Screw holes

Place six (6) screws into the holes indicated by circles to secure the
motherboard to the chassis.

Do not overtighten the screws! Doing so may damage the
motherboard.

Place this side towards
the rear of the chassis

Figure 2-1 Motherboard placement and screw holes

ASUS P4B-LS motherboard user guide

2-1

2.2 Motherboard layout

22cm (8.7in)

PS/2KBMS

T: Mouse
B: Keyboard

USB1
USB2

COM1

PARALLEL PORT

COM2

Line
Out

Line

In

Mic

In

GAME_AUDIO

MICF

SPEAKER

AAPANEL

CD1
AUX

Audio
Codec

MODEM

SPDIFOUT

AUD_EN1

USB2

FUSB

Socket 478

ATX12V

Accelerated Graphics Port

PCI1

PCI2

PCI3

PCI4

LED1

ASUS Proprietary Expansion Slot

PCI6

CNR

Intel 845

Memory

Controller

Hub (MCH)

(AGP+1.5V)

PWR_FAN

CPU_FAN

OVER_VOLT

WARNING

CR2032 3V
Lithium Cell

CMOS Power

Intel I/O

Controller

Hub

(ICH2)

Super

ASUS

ASIC

with

Hardware

Monitor

SDRVOL

USBPWR1

AUX+12V

ATX Power Connector

DIMM Socket 1 (64/72-bit, 168-pin module)

DIMM Socket 2 (64/72-bit, 168-pin module)

DIMM Socket 3 (64/72-bit, 168-pin module)

0 1

2 3

4 5

SECONDARY IDE

FLOPPY

PRIMARY IDE

®

P4B-LS

MS

SD

CLRCMOS

SWITCH

SMART

JEN

SPEECH

AFPANEL

PANEL

I/O

Firmware

SMARTCON

CHA_FAN

2Mbit

Hub

CHASSIS

SMB

KBPWR

30.5cm (12.0in)

Figure 2-2 Motherboard Layout

The audio CODEC, external GAME/AUDIO connectors, internal audio
connectors are optional components, and present in audio models
only. The components are grayed in the above motherboard layout.

For System Integrators:
The SD and MS connectors may or may not be mounted depending on
required specifications.

2-2

Chapter 2: Hardware information

2.3 Before you proceed

Take note of the following precautions before you install motherboard
components or change any motherboard settings.

1. Unplug the power cord from the wall socket before touching any
component.

2. Use a grounded wrist strap or touch a safely grounded object or to
a metal object, such as the power supply case, before handling
components to avoid damaging them due to static electricity.

3. Hold components by the edges and do not to touch the ICs on them.

4. Whenever you uninstall any component, place it on a grounded
antistatic pad or in the bag that came with the component.

5. Before you install or remove any component, ensure that the

ATX power supply is switched off or the power cord is
detached from the power supply. Failure to do so may cause

severe damage to the motherboard, peripherals, and/or
components.

When lit, the green LED (LED1) indicates that the system is ON, in
sleep mode, or in soft-off mode, a reminder that you should shut down
the system before removing of plugging in any motherboard
component.

The red LED (WARNING) is a smart protection from motherboard burn
out caused by an incorrect AGP card. If you plug in any 3.3V AGP card
into the 1.5V AGP slot, this LED lights up thus preventing the system to
power up. This LED remains off if you plug in a 1.5V AGP card.
(This feature is present on PCB R1.05 and later versions.)

WARNING

P4B-LS

ON

®

Incorrect

AGP Card

LED1

OFF

Correct

AGP Card

ON

P4B-LS Onboard LED

Standby

Power

Figure 2-3 Onboard LEDs

ASUS P4B-LS motherboard user guide

OFF

Powered

Off

2-3

2.4 Central Processing Unit (CPU)

2.4.1 Overview

The motherboard comes with a surface mount 478-pin Zero Insertion
Force (ZIF) socket. This socket is specifically designed for the Intel
Pentium® 4 478/Northwood Processor.

The Intel Pentium 4 Processor in the 478-pin package uses the Flip-Chip
Pin Grid Array 2 (FC-PGA2) package technology, and includes the Intel
NetBurst™ micro-architecture. The Intel NetBurst micro-architecture
features the hyper-pipelined technology, rapid execution engine, 400MHz
system bus, and execution trace cache. Together, these attributes improve
system performance by allowing higher processor frequencies, faster
execution of integer instructions, and a data transfer rate of 3.2GB/s.

Gold Mark

®

®

Figure 2-4 Intel Pentium 4 478/Northwood Processor

Note in the illustration that the CPU has a gold triangular mark on one
corner. This mark indicates the processor Pin 1 that should match a
specific corner of the CPU socket.

Incorrect installation of the CPU into the socket may bend the pins and
severely damage the CPU!

2-4

Chapter 2: Hardware information

2.4.2 Installing the CPU

Follow these steps to install a CPU.

1. Locate the 478-pin ZIF socket on the motherboard.

Figure 2-5 Intel 478-pin ZIF Socket

2. Unlock the socket by pressing the lever sideways, then lift it up to a
90°-100° angle.

Socket Lever

90 -100

Figure 2-6 CPU Socket Lever at 90° -100° Angle

Make sure that the socket lever is lifted up to 90°-100° angle,
otherwise the CPU does not fit in completely.

ASUS P4B-LS motherboard user guide

2-5

3. Position the CPU above the socket such that its marked corner
matches the base of the socket lever.

4. Carefully insert the CPU into the socket until it fits in place.

The CPU fits only in one correct orientation. DO NOT force the CPU
into the socket to prevent bending the pins and damaging the CPU!

Gold Mark

Figure 2-7 Installing the CPU

5. When the CPU is in place, press it firmly on the socket while you push
down the socket lever to secure the CPU. The lever clicks on the side
tab to indicate that it is locked.

Figure 2-8 Installed CPU

2-6

Chapter 2: Hardware information

2.4.3 Installing the heatsink and fan

The Intel® Pentium® 4 478/Northwood Processor requires a specially
designed heatsink and fan assembly to ensure optimum thermal condition
and performance.

When you buy a boxed Intel Pentium 4 478/Northwood Processor, the
package includes the heatsink, fan, and retention mechanism.

In case you buy a CPU separately, make sure that you use only Intel
certified heatsink and fan.

Follow these steps to install the CPU heatsink and fan.

1. Place the heatsink on top of the installed CPU, making sure that the
heatsink fits properly on the retention module base.

The retention module base is already installed on the motherboard.

CPU Heatsink

Retention Module Base

Figure 2-9 Installing the CPU Heatsink

Your boxed Intel Pentium 4 478/Northwood Processor package should
come with installation instructions for the CPU, heatsink, and the
retention mechanism. If the instructions in this section do not match the
CPU documentation, follow the latter.

ASUS P4B-LS motherboard user guide

2-7

2. Position the fan with the retention mechanism on top of the heatsink.
Align and snap the four hooks of the retention mechanism to the holes
on each corner of the module base.

Make sure that the fan and retention mechanism assembly perfectly
fits the heatsink and module base, otherwise you cannot snap the
hooks into the holes.

Retention Hole

Retention Lock

Retention Hook Snapped
to the Retention Hole

Figure 2-10 Installing the Fan and Retention Mechanism

Keep the retention locks lifted upward while fitting the retention
mechanism to the module base.

2-8

Chapter 2: Hardware information

3. Push down the locks on the retention mechanism to secure the
heatsink and fan to the module base.

When secure, the retention locks should point to opposite directions.

Figure 2-11 Fan and Retention Mechanism Installed and Locked

2.4.4 Connecting the CPU fan cable

When the fan, heatsink, and the retention mechanism are in place,
connect the CPU fan cable to the connector on the motherboard labeled
CPU_FAN.

CPU Fan Connector
(CPU_FAN)

Figure 2-12 CPU Fan Connector

Don’t forget to connect the CPU fan connector! Hardware monitoring
errors may occur if you fail to plug this connector.

ASUS P4B-LS motherboard user guide

2-9

2.5 System memory

2.5.1 Overview

The motherboard comes with three Single Data Rate (SDR) Dual Inline
Memory Module (DIMM) sockets. These sockets support up to 3GB
system memory using unbuffered ECC or non-ECC PC100/133 DIMMs.

88 Pins

®

P4B-LS

60 Pins

20 Pins

P4B-LS 168-Pin DIMM Sockets

Figure 2-13 DIMM Sockets Location and SDR DIMMs

DIMMs are keyed with notches so that they fit in only one direction. DO
NOT force a DIMM into a socket to avoid damaging the DIMM.

2.5.2 Memory configurations

Install DIMMs in any of the following combinations.

DIMM Location 168-pin DIMM (SDR) Total Memory

Socket 1 (Rows 0&1) 64MB, 128MB, 256MB, 512MB, 1GB x1
Socket 2 (Rows 2&3) 64MB, 128MB, 256MB, 512MB, 1GB x1

2-10

Socket 3 (Rows 4&5) 64MB, 128MB, 256MB, 512MB, 1GB x1

Total system memory (Max. 3GB) =

Chapter 2: Hardware information

2.5.3 Installing a DIMM

Make sure to unplug the power supply before adding or removing
DIMMs or other system components. Failure to do so may cause
severe damage to both the motherboard and the components.

Follow these steps to install a DIMM.

1. Unlock a DIMM socket by pressing the retaining clips outward.

2. Align a DIMM on the socket such that the notches on the DIMM match
the breaks on the socket.

3. Firmly insert the DIMM into the socket until the retaining clips snap
back in place and the DIMM is properly seated.

Figure 2-14 Installing a DIMM

Figure 2-15 Installed DIMM

Unlocked Retaining Clip

Locked Retaining Clip

ASUS P4B-LS motherboard user guide

2-11

2.5.4 Removing a DIMM

Follow these steps to remove a DIMM.

1. Simultaneously press the retaining clips outward to unlock the DIMM.

Support the DIMM lightly with your fingers when pressing the retaining
clips. The DIMM might get damaged when it flips out with extra force.

2. Remove the DIMM from the socket.

Figure 2-16 Removing a DIMM

2-12

Chapter 2: Hardware information

2.6 Expansion slots

In the future, you may need to install expansion cards. The motherboard
has five standard PCI slots, one ASUS proprietary expansion slot, one
Accelerated Graphics Port (AGP) slot, and a Communications and
Networking Riser (CNR) slot. The following sub-sections describe the slots
and the expansion cards that they support.

Make sure to unplug the power cord before adding or removing
expansion cards. Failure to do so may cause you physical injury and
damage motherboard components.

2.6.1 Installing an expansion card

Follow these steps to install an expansion card.

1. Before installing the expansion card, read the documentation that
came with it and make the necessary hardware settings for the card.

2. Remove the system unit cover (if your motherboard is already installed
in a chassis).

3. Remove the bracket opposite the slot that you intend to use. Keep the
screw for later use.

4. Align the card connector with the slot and press firmly until the card is
completely seated on the slot.

5. Secure the card to the chassis with the screw you removed earlier.

6. Replace the system cover.

Figure 2-17 Installed PCI Card

ASUS P4B-LS motherboard user guide

2-13

2.6.2 Configuring an expansion card

After physically installing the expansion card, configure the card by
adjusting the software settings.

1. Turn on the system and change the necessary BIOS settings, if any.
See Chapter 4 for information on BIOS setup.

2. Assign an IRQ to the card. Refer to the tables below.

3. Install the software drivers for the expansion card.

Standard Interrupt Assignments

IRQ Priority Standard Function

0 1 System Timer
1 2 Keyboard Controller
2 N/A Programmable Interrupt
3* 11 Communications Port (COM2)
4* 12 Communications Port (COM1)
5* 13 Sound Card (sometimes LPT2)
6 14 Floppy Disk Controller
7* 15 Printer Port (LPT1)
8 3 System CMOS/Real Time Clock
9* 4 ACPI Mode when used
10* 5 IRQ Holder for PCI Steering
11* 6 IRQ Holder for PCI Steering
12* 7 PS/2 Compatible Mouse Port
13 8 Numeric Data Processor
14* 9 Primary IDE Channel
15* 10 Secondary IDE Channel

*These IRQs are usually available for ISA or PCI devices.

IRQ assignments for this motherboard

ABCDEFGH

PCI slot 1 — — — — — shared — —
PCI slot 2 — — — — — — shared —
PCI slot 3 — — — — — — — shared
PCI slot 4 — — — — shared — — —
PCI slot 5 (LAN/SCSI slot) — — — — shared shared shared —
PCI slot 6 — — used — — — — —
Onboard USB controller HC0 — — — used — — — —
Onboard USB controller HC1 — — — — — — — shared
AGP used — — — — — — —
CNR LAN — — — — shared — — —
CNR Audio/Modem — used — — — — — —
Onboard Audio — — — — — shared — —

When using PCI cards on shared slots, ensure that the drivers support
“Share IRQ” or that the cards do not need IRQ assignments.
Otherwise, conflicts will arise between the two PCI groups, making the
system unstable and the card inoperable.

2-14

Chapter 2: Hardware information

2.6.3 PCI slots and ASUS proprietary slot

There are five standard 32-bit PCI slots and an ASUS proprietary
LAN/SCSI slot in this motherboard. The standard slots support PCI cards
such as a LAN card, SCSI card, USB card, and other cards that comply
with PCI specifications.

The LAN/SCSI slot supports the ASUS LS99 LAN/SCSI card. Refer to the
user’s manual that came with the card for more information and card
configuration.

Figure 2-18 ASUS LS99 LAN/SCSI Card

2.6.4 AGP slot

This motherboard has an Accelerated Graphics Port (AGP) slot that
supports +1.5V AGP cards. When you buy an AGP card, make sure that
you ask for one with +1.5V specification. Note the notches on the card
golden fingers to ensure that they fit the AGP slot on your motherboard.

The AGP slot supports only 1.5V AGP cards. NEVER install a SiS305­based AGP card or any other 3.3V AGP card into the slot. Doing so will
severely damage the motherboard!

®

P4B-LS

Keyed for 1.5V

P4B-LS Accelerated Graphics Port (AGP) Slot

Figure 2-19 Accelerated Graphics Port (AGP) Slot Location

ASUS P4B-LS motherboard user guide

2-15

2.6.5 CNR slot

The Communications and Networking Riser (CNR) slot supports interface
cards that integrates audio, modem, and network functionality.

The CNR specification supports interfaces including:

• Audio Codec ‘97 (AC ’97) - for audio and/or modem functions

• Local Area Network (LAN) - for networking functions

• Universal Serial Bus (USB) - for functions implemented in the USB

interface, and technologies such as broadband, DSL, and wireless

• System Management Bus (SMB) - for Plug-n-Play functionality

• Power - to provide the signals required for power management, and the

main power supplies to operate the CNR circuitry

The CNR is tagged to replace the current Audio Modem Riser (AMR) slot
because of its flexibility and added features. Also, the CNR slot does not
take up the motherboard space for one PCI slot because it is a shared
slot; rather, it provides you more options.

®

P4B-LS

P4B-LS Communication & Networking
Riser Slot

Figure 2-20 Communications and Networking Riser (CNR) Slot

Location

2-16

Chapter 2: Hardware information

2.7 Switches and jumpers

The motherboard frequency is adjusted through the DIP switches. The
white block represents the switch position. The illustration below shows all
the switches in the OFF position.

SWITCH

®

P4B-LS

P4B-LS DIP Switches

Figure 2-21 DIP Switches

The JEN jumper must be set to pins 1-2 (jumper mode) if you wish to
use the DIP switches. Otherwise, setting the switches does not
produce any effect.

1. JumperFree™ mode (JEN)

12345678910

ONOFF

ON

1. Frequency Multiple

2. Frequency Multiple

3. Frequency Multiple

4. Frequency Multiple

5. Frequency Selection

6. Frequency Selection

7. Frequency Selection

8. Frequency Selection

9. Frequency Selection

10. Reserved

This jumper allows you to enable or disable the JumperFree™ mode.
The JumperFree mode allows you to change CPU settings through the
BIOS setup instead of using the DIP switches.

OFF

ON

12345678910

3
2

Jumper Free

(Default)

SWITCH

®

P4B-LS

P4B-LS JumperFree™ Mode Setting

JEN

2
1

Jumper Mode

Figure 2-22 JumperFree Mode Setting

The JEN jumper is set in conjunction with the DIP switches. In
JumperFree mode, set all the DIP switches to OFF.

ASUS P4B-LS motherboard user guide

2-17

2. CPU Core:Bus frequency multiple (SWITCH Switches 1-4)

This option sets the frequency multiple between the CPU internal and
external frequencies. This must be set in conjunction with the CPU Bus
Frequency.

ON

12345678910

SWITCH

ON

12345678910

ON

12345678910

ON

12345678910

®

P4B-LS

P4B-LS CPU Frequency
Multiple Selection

8.0x

12345678910

13.0x

12345678910

17.0x

12345678910

ON

ON

ON

10.0x

12345678910

14.0x

12345678910

18.0x

12345678910

ON

ON

ON

11.0x

12345678910

15.0x

12345678910

19.0x

12345678910

ON

ON

ON

12.0x

12345678910

16.0x

12345678910

20.0x

12345678910

ON

ON

ON

21.0x

Figure 2-23 CPU Core:Bus Frequency Multiple

Make sure that the JEN jumper is set to jumper mode before setting
the above switches.

The option to set the CPU core:bus frequency multiple is available only
on unlocked CPUs. If you are using a locked CPU, setting the switches
does not produce any effect.

2-18

Chapter 2: Hardware information

22.0x

23.0x

24.0x

3. CPU frequency selection (SWITCH Switches 5-9)

This option tells the clock generator what frequency to send the CPU.
This allows the selection of the CPU’s external frequency (or Bus
Clock). The BUS Clock multiplied by the Frequency Multiple equals the
CPU’s internal frequency (the advertised CPU speed).

To select the CPU external frequency using the DIP switches, ensure
that the JEN jumper is set to jumper mode.

12345678910

100MHz

CPU

33MHz 35MHz 37MHz 40MHz

PCI

12345678910

120MHz

CPU

30MHz 31MHz 33MHz

PCI

P4B-LS CPU

P4B-LS

SWITCH

®

External Frequency Selection

Figure 2-24 CPU Frequency Settings

ON

ON

12345678910

105MHz

12345678910

125MHz

ON

ON

12345678910

111MHz

12345678910

133MHz

ON

ON

12345678910

120MHz

ON

Set the CPU frequency only to the recommended settings.
Frequencies other than the recommended CPU bus frequencies are
not guaranteed to be stable.

ASUS P4B-LS motherboard user guide

2-19

4. Audio controller (AUD_EN1)

(on audio models only)

This jumper allows you to enable or disable the audio CODEC on the
motherboard. Disable the audio CODEC if you desire to install a PCI
audio card on one of the PCI slots or on the CNR slot. The default
setting is Enable.

AUD_EN1

®

P4B-LS

12

Enable

(Default)

23

Disable

P4B-LS Audio Codec Setting

Figure 2-25 Audio CODEC Settings

5. Keyboard power (KBPWR)

This jumper allows you to enable or disable the keyboard wake-up
feature. Set this jumper to pins 1-2 (+5VSB) if you wish to wake up the
computer when you press a key on the keyboard (the default is the
Space Bar). This feature requires an ATX power supply that can supply
at least 1A on the +5VSB lead, and a corresponding setting in the
BIOS (see section 4.5.1 Power Up Control). The default is setting is on
pins 1-2 (+5VSB).

®

P4B-LS

P4B-LS Keyboard Power Setting

Figure 2-26 Keyboard Power Settings

2-20

KBPWR

12

+5VSB

(Default)

23

+5V

Chapter 2: Hardware information

6. USB device wake-up (USBPWR, FUSB)

Set these jumpers to +5V to wake up the computer from S1 sleep
mode (CPU stopped, DRAM refreshed, system running in low power
mode) using the connected USB devices. Set to +5VSB to wake up
from S3 sleep mode (no power to CPU, DRAM in slow refresh, power
supply in reduced power mode). Both jumpers are set to pins 2-3 (+5V)
by default because not all computers have the appropriate power
supply to support this feature.

The USBPWR jumper is for the rear USB ports. The FUSB jumper is
for the internal USB header that you can connect to the front USB
ports.

1. This feature requires a power supply that can provide at least 1A
on the +5VSB lead when these jumpers are set to +5VSB.
Otherwise, the system does not power up.

2. The total current consumed must NOT exceed the power supply
capability (+5VSB) whether under normal condition or in sleep
mode.

USBPWR

2

1

+5VSB

P4B-LS

®

FUSB

2

1

P4B-LS USB Device Wake Up

+5VSB +5V

Figure 2-27 USB Device Wake-up Settings

2

3

+5V

(Default)

2

3

(Default)

ASUS P4B-LS motherboard user guide

2-21

7. SDRAM voltage (SDRVOL)

This jumper allows you to select the voltage supplied to the system
memory. The default setting is on pins 1-2 (3.4V).

SDRVOL

3

4

3.6 V

P4B-LS

®

12

3.4 V 3.5 V

(Default)

2

3

P4B-LS SDR Voltage Setting

Figure 2-28 SDRAM Voltage Settings

8. Speaker selector (SPEECH)

(on audio models only)

This jumper allows you to select the speaker you wish to use for the
ASUS POST Reporter™ function. Set to pins 1-2 to use the internal
speaker (usually included in the chassis). Set to pins 2-3 if you
connected an external speaker to the Line Out jack (lime color) on the
rear panel.

®

P4B-LS

P4B-LS Speaker Selector

SPEECH

2
1

BUZZER

3
2

LINEOUT

(Default)

Figure 2-29 Speaker Selection Settings

2-22

Chapter 2: Hardware information

9. VCORE over-voltage (OVER_VOLT)

When enabled, this jumper allows a CPU Vcore setting range of
+1.75V to +2.1V for P4 Willamette processor, and a 1.475V to 1.75V
range for Northwood processor through BIOS Setup. When disabled,
the allowed Vcore settings are lower. (This feature is present on PCB
R1.05 or later versions.)

Setting to a very high core voltage may cause permanent damage to
the CPU. It is recommended that you keep the default setting
(Disable).

OVER_VOLT

®

P4B-LS

P4B-LS OVER_VOLT Setting

12

Disable

(Default)

23

Enable

10.Clear RTC RAM (CLRCMOS)

This jumper allows you to clear the Real Time Clock (RTC) RAM in
CMOS. You can clear the CMOS memory of date, time, and system
setup parameters by erasing the CMOS RTC RAM data. The RAM
data in CMOS, that include system setup information such as system
passwords, is powered by the onboard button cell battery.

To erase the RTC RAM:

1. Turn OFF the computer and unplug the power cord.

2. Remove the battery.

3. Place a jumper cap over the pins for a few seconds to short the
jumper. Remove the jumper cap.

4. Re-install the battery.

5. Plug the power cord and turn ON the computer.

6. Hold down the <Del> key during the boot process and enter BIOS
setup to re-enter data.

Refer to the illustration on the next page showing the CLRCMOS
location on the motherboard.

ASUS P4B-LS motherboard user guide

2-23

P4B-LS

®

Intel I/O

Controller

Hub

(ICH2)

P4B-LS Clear RTC RAM

CLRCMOS

Figure 2-30 Clear RTC RAM

2.8 Connectors

This section describes and illustrates the internal connectors on the
motherboard.

Some pins are used for connectors or power sources. These are
clearly distinguished from jumpers in the Motherboard Layout. Placing
jumper caps over these connector pins will cause damage to your
motherboard.

Always connect ribbon cables with the red stripe to Pin 1 on the
connectors. Pin 1 is usually on the side closest to the power connector
on hard drives and CD-ROM drives, but may be on the opposite side
on floppy disk drives.

1. Hard disk activity LED (2-pin HDLED)

This connector supplies power to the hard disk activity LED. The read
or write activities of any device connected to the primary or secondary
IDE connector cause this LED to light up.

P4B-LS

®

TIP: If the case-mounted LED does not
light up, try reversing the 2-pin plug.

HDLED

P4B-LS HD Activity LED

Figure 2-31 Hard Disk LED Connector

2-24

Chapter 2: Hardware information

2. Primary/Secondary IDE connectors (40-1 pin IDE1/IDE2)

This connector supports the provided UltraDMA/100/66 IDE hard disk
ribbon cable. Connect the cable’s blue connector to the primary
(recommended) or secondary IDE connector, then connect the gray
connector to the UltraDMA/100/66 slave device (hard disk drive) and
the black connector to the UltraDMA/100/66 master device. It is
recommended that you connect non-UltraDMA/100/66 devices to the
secondary IDE connector. If you install two hard disks, you must
configure the second drive as a slave device by setting its jumper
accordingly. Refer to the hard disk documentation for the jumper
settings. BIOS supports specific device bootup. If you have more than
two UltraDMA/100/66 devices, purchase another UltraDMA/100/66
cable. You may configure two hard disks to be both master devices
with two ribbon cables – one for the primary IDE connector and
another for the secondary IDE connector.

1. Pin 20 on each IDE connector is removed to match the covered
hole on the UltraDMA cable connector. This prevents incorrect
orientation when you connect the cables.

2. The hole near the blue connector on the UltraDMA/100/66 cable is
intentional.

®

P4B-LS

P4B-LS IDE Connectors

Figure 2-32 IDE Connectors

For UltraDMA/100/66 IDE devices, use an 80-conductor IDE cable. The
UltraDMA/66 cable included in the motherboard package also supports
UltraDMA/100.

NOTE: Orient the red markings
(usually zigzag) on the IDE
ribbon cable to PIN 1.

Secondary IDE Connector

PIN 1

Primary IDE Connector

ASUS P4B-LS motherboard user guide

2-25

3. Floppy disk drive connector (34-1 pin FLOPPY)

This connector supports the provided floppy drive ribbon cable. After
connecting one end to the motherboard, connect the other end to the
floppy drive. (Pin 5 is removed to prevent incorrect insertion when
using ribbon cables with pin 5 plug).

FLOPPY

PIN 1

NOTE: Orient the red markings on
the floppy ribbon cable to PIN 1.

P4B-LS

®

P4B-LS Floppy Disk Drive Connector

Figure 2-33 Floppy Disk Drive Connector

4. Chassis open alarm lead (4-1 pin CHASSIS)

This lead is for a chassis designed with intrusion detection feature.
This requires an external detection mechanism such as a chassis
intrusion sensor or microswitch. When you remove any chassis
component, the sensor triggers and sends a high-level signal to this
lead to record a chassis intrusion event.

If you do not wish to use the chassis intrusion lead, place a jumper cap
over the pins labeled “Chassis Signal” and “Ground” to close the
circuit.

®

P4B-LS

P4B-LS Chassis Alarm Lead

Figure 2-34 Chassis Alarm Lead

2-26

CHASSIS

+5VSB_MB

Chassis Signal

GND

1

Chapter 2: Hardware information

5. CPU, Chassis, and Power Fan Connectors
(3-pin CPU_FAN, CHA_FAN, PWR_FAN)

The three fan connectors support cooling fans of 350mA (4.2 Watts) or
a total of 1A (12W) at +12V. Orient the fans so that the heat sink fins
allow air flow to go across the onboard heat sinks instead of the
expansion slots. The fan wiring and plug may vary depending on the
fan manufacturer. Connect the fan cable to the connector matching the
black wire to the ground pin.

Do not forget to connect the fan cables to the fan connectors. Lack of
sufficient air flow within the system may damage the motherboard
components. These are not jumpers! DO NOT place jumper caps on
the fan connectors!

GND

+12V

Rotation

GND

+12V

Rotation

P4B-LS

PWR_FAN

®

CPU_FAN

CHA_FAN

GND

P4B-LS 12-Volt Fan Connectors

+12V

Rotation

Figure 2-35 CPU, Chassis, and Power Fan Connectors

6. USB Header (10-1 pin USB2)

If the USB port connectors on the rear panel are inadequate, a USB
header is available for two additional USB port connectors. Connect a
2-port USB connector set to the USB header and mount the USB
bracket to an open slot in the chassis.

USB2

P4B-LS

®

1: USB Power
2: USBP2–
3: USBP2+
4: GND
5: NC

610
15

6: USB Power
7: USBP3–
8: USBP3+
9: GND

P4B-LS USB Header

Figure 2-36 USB Header

ASUS P4B-LS motherboard user guide

2-27

7. ASUS EZPlug™ and ATX power connectors
(20-pin ATXPWR, 4-pin ATX+12V, 4-pin AUX+12V)

These connectors connect to an ATX +12V power supply . The plugs
from the power supply are designed to fit these connectors in only one
orientation. Find the proper orientation and push down firmly until the
connectors completely fit.

In addition to the 20-pin ATXPWR connector, this motherboard requires
that you connect the 4-pin ATX +12V power plug to provide sufficient
power to the CPU.

If you are using a standard ATX power supply that does not have the
ATX +12V plug, connect one 4-pin device power plug to the ASUS EZ
Plug™ connector labeled AUX +12V.

Make sure that your ATX +12V power supply can provide 8A on the
+12V lead and at least 1A on the +5-volt standby lead (+5VSB). The
minimum recommended wattage is 230W, or 300W for a fully
configured system. The system may become unstable and may
experience difficulty powering up if the power supply is inadequate.

+3.3VDC

-12.0VDC
COM

PS_ON#

COM
COM
COM

-5.0VDC
+5.0VDC
+5.0VDC

P4B-LS

ATXPWR

®

ATX+12V

P4B-LS ATX & Auxiliary Power Connectors

Figure 2-37 Power Supply Connectors

+3.3VDC
+3.3VDC
COM
+5.0VDC
COM
+5.0VDC
COM
PWR_OK
+5VSB
+12.0VDC

+12V DC COM

+12V DC COM

ASUS EZPlug™
(AUX+12V)

+5V
GND
GND

+12V

2-28

Chapter 2: Hardware information

8. SMBus connector (6-1 pin SMB)

This connector allows you to connect SMBus (System Management
Bus) devices. Devices communicate with an SMBus host and/or other
SMBus devices using the SMBus interface. SMBus is a specific
implementation of an I

2

C bus, a multi-device bus that allows multiple
chips to connect to the same bus and enable each one to act as a
master by initiating data transfer.

®

P4B-LS

P4B-LS SMBus Connector

1

SMB

SMBCLK

FLOATING

+3V

Ground

SMBDATA

Figure 2-38 SMBus Connector

9. Internal audio connectors (4-pin CD1, AUX, MODEM)

(optional)

These connectors allow you to receive stereo audio input from sound
sources such as a CD-ROM, TV tuner, or MPEG card. The MODEM
connector allows the onboard audio to interface with a voice modem
card with a similar connector. It also allows the sharing of mono_in
(such as a phone) and a mono_out (such as a speaker) between the
audio and a voice modem card.

CD1 (Black)
AUX (White)

®

P4B-LS

MODEM

Ground

Ground

Left Audio Channel

Right Audio Channel

P4B-LS Internal Audio Connectors

Modem-Out

Figure 2-39 Internal Audio Connectors

ASUS P4B-LS motherboard user guide

Ground

Ground

Modem-In

2-29

10.Front panel audio connectors (3-pin MICF, 3-pin SPEAKER)

(optional)

These connectors connect to an optional front panel audio module
using two 3-pin audio cables. If your chassis has this audio module,
you may conveniently connect a microphone and a speaker/
headphone on the front panel.

The front panel microphone and speaker may not work properly if there
is another microphone connected to the Microphone (pink) jack and a
speaker on the Line Out (lime) jack on the rear panel. You may only
use one microphone and one speaker/headphone at a time.

MIC Power

MIC Input

Ground

®

P4B-LS

P4B-LS Front Panel Audio Connectors

1

1

MICF
SPEAKER

Ground

Left SPKR_OUT

Right SPKR_OUT

Figure 2-40 Front Panel Audio Connectors

11. ASUS iPanel audio connector (10-1 pin AAPANEL)

(optional)

This connector accommodates the audio cable from the optional ASUS
iPanel. The audio connectors on the iPanel allow you convenient audio
control from the front panel.

AAPANEL

Line in_R

Line out_R

P4B-LS

®

P4B-LS Audio Panel Connector

Figure 2-41 ASUS iPanel Audio Connector

2-30

Line in_L

AGND

AGND2AGND3

MIC2

MICPWR

Line out_L

Chapter 2: Hardware information

12.ASUS iPanel connector (24-1 pin AFPANEL)

(optional)

This connector allows you to connect an optional ASUS iPanel, an
easy-to-access drive bay with front I/O ports and status LEDs. If you
are not using an ASUS iPanel, you can connect an optional wireless
transmitting and receiving infrared module to the SIR connector.

AFPANEL

®

P4B-LS

P4B-LS iPanel Connector

SIR
CIR

+5 V

IRRX

NC

NC

GND

+5 V

IRRX

NC

NC

GND

IR_CON

GND

IRTX

CIRRX

+5VSB

GND

IRTX

CIRRX

+5VSB

SMBDATA

+3VSB

EXTSMI#

CHASSIS#

NCNCNC

+5V SMBCLK

MLED-

PCIRST#

NC

NC

BATT

Standard Infrared (SIR)

Front View Back View

IRTX
GND

+5V
(NC)

IRRX

Figure 2-42 ASUS iPanel Connector

13.Digital audio connector (4-1 pin SPDIFOUT)

(optional)

This connector connects an SPDIF audio module that allows digital
instead of analog sound output. Connect one end of the audio cable to
the SPDIFOUT connector on the motherboard, and the other end to
the SPDIF module.

®

P4B-LS

SPDIFOUT

GND

SPDIFOUT

+5V

P4B-LS Digital Audio Connector

Figure 2-43 Digital Audio Connector

ASUS P4B-LS motherboard user guide

2-31

14.Smart Card Reader connector (14-1 pin SMARTCON)

(optional)

This connector accommodates a Smart Card Reader that allows you to
conveniently make transactions such as financial, health care,
telephony, or traveling services through a Smart Card user interface
software.

SMARTCON

®

P4B-LS

NC

SCRCLK

SCRFET#

RFU2

SCRREST

NC

VCC

1

LED

P4B-LS Smartcard

GND

NC2

SCRRES#

RFU1

SCRUI

Figure 2-44 Smart Card Reader Connector

15.SD and MS connectors (10-pin SD, MS)*

These connectors support the sophisticated memory devices called
Secure Digital (SD) memory card and Memory Stick (MS). These
devices facilitate fast and secure downloading of all types of digital files
such as photos, music, news, and movies. You may also use SD and
MS to directly record audio, video, and still photos. The SD and MS are
non-volatile devices so they do not require power to retain the
information stored in them.

The SD and MS connectors may or may not be mounted depending on SI requirements.

*

You need an SD/MS reader to use the SD and MS devices. The SD,
MS, and the SD/MS reader are optional items and may be purchased
separately.

MS

SD

GND
MSDA1
+3V
MSDA2
SDA3
SDA4
SDA5
SDACLK
SDAPWCTL#
SDALED

1

®

P4B-LS

P4B-LS SD MS Connectors

GND

SDB1

+3V
SDB2
SDB3
SDB4
SDB5

SDBCLK

SDBPWCTL#

SDBLED

1

Figure 2-45 Secure Digital (SD) Memory Card and

Memory Stick (MS) Connectors

2-32

Chapter 2: Hardware information

16.Power supply thermal connector (2-pin TRPWR)

If your power supply has a thermal monitoring feature, connect its
thermal sensor cable to this connector.

®

P4B-LS

Ground
TRPWR

P4B-LS Power Supply Thermal Connector

Figure 2-46 Power Supply Thermal Connector

17.System panel connector (20-pin PANEL)

This connector accommodates several system front panel functions.

TRPWR

PLED

Keylock

MLED

ExtSMI#

Ground

Ground

Speaker
Connector

Ground

Speaker

Ground

+5V

PWR

Reset

Ground

Ground

Reset SW

ATX Power
Switch*

®

P4B-LS

P4B-LS System Panel Connectors

Keyboard Lock

Power LED

+5 V

+5 V

Message LED

SMI Lead

*

Requires an ATX power supply.

Figure 2-47 System Panel Connector

• System Power LED Lead (3-1 pin PLED)

This 3-1 pin connector connects to the system power LED. The LED
lights up when you turn on the system power, and blinks when the
system is in sleep mode.

• Keyboard Lock Lead (2-pin KEYLOCK)

This 2-pin connector connects to a chassis-mounted switch to allow
the use of the keyboard lock feature.

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2-33

• System Warning Speaker Lead (4-pin SPEAKER)

This 4-pin connector connects to the case-mounted speaker and
allows you to hear system beeps and warnings.

• System Message LED Lead (2-pin MLED)

This 2-pin connector is for the system message LED that indicates
receipt of messages from a fax/modem. The normal status for this LED
is ON, when there is no incoming data signal. The LED blinks when
data is received. The system message LED feature requires an ACPI
OS and driver support.

• System Management Interrupt Lead (2-pin SMI)

This 2-pin connector allows you to manually place the system into a
suspend mode, or “green” mode, where system activity is instantly
decreased to save power and to expand the life of certain system
components. Attach the case-mounted suspend switch to this 2-pin
connector.

• ATX Power Switch / Soft-Off Switch Lead (2-pin PWRBTN)

This connector connects a switch that controls the system power.
Pressing the power switch turns the system between ON and SLEEP,
or ON and SOFT OFF, depending on the BIOS or OS settings.
Pressing the power switch while in the ON mode for more than 4
seconds turns the system OFF.

• Reset Switch Lead (2-pin RESET)

This 2-pin connector connects to the case-mounted reset switch for
rebooting the system without turning off the system power.

2-34

Chapter 2: Hardware information

Chapter 3

This chapter describes the power up
sequence and gives information on the
BIOS beep codes.

Powering up

ASUS P4B-LS motherboard

3.1 Starting up for the first time

1. After making all the connections, replace the system case cover.

2. Be sure that all switches are off.

3. Connect the power cord to the power connector at the back of the
system chassis.

4. Connect the power cord to a power outlet that is equipped with a surge
protector.

5. Turn on the devices in the following order:

a. Monitor
b. External SCSI devices (starting with the last device on the chain)
c. System power (if you are using an ATX power supply, you need to

switch on the power supply as well as press the ATX power switch
on the front of the chassis).

6. After applying power, the power LED on the system front panel case
lights up. For ATX power supplies, the system LED lights up when you
press the ATX power switch. If your monitor complies with “green”
standards or if it has a “power standby” feature, the monitor LED may
light up or switch between orange and green after the system LED
turns on. The system then runs the power-on tests. While the tests are
running, the BIOS beeps or additional messages appear on the
screen. If you do not see anything within 30 seconds from the time you
turned on the power, the system may have failed a power-on test.
Check the jumper settings and connections or call your retailer for
assistance.

Award BIOS Beep Codes

Beep Meaning

One short beep when No error during POST
displaying logo

Long beeps in an endless loop No DRAM installed or detected
One long beep followed by Video card not found or video card

three short beeps memory bad
High frequency beeps when CPU overheated;

system is working System running at a lower frequency

You will not hear the BIOS beeps when the ASUS POST Reporter is
enabled. You will hear the vocal POST messages instead.

7. At power on, hold down <Delete> to enter BIOS Setup. Follow the
instructions in Chapter 4.

ASUS P4B-LS motherboard user guide

3-1

3.2 Vocal POST Messages

This motherboard includes the Winbond speech controller to support a
special feature called the ASUS POST Reporter™. This feature gives you
vocal POST messages and alerts to inform you of system events and boot
status. In case of a boot failure, you will hear the specific cause of the
problem.

These POST messages are customizable using the Winbond Voice Editor
software that came with your package. You can record your own
messages to replace the default messages.

Following is a list of the default POST messages and their corresponding
actions, if any.

POST Message Action

No CPU installed • Install an Intel Pentium 4

478/Northwood Processor into the
CPU socket.

System failed CPU test • Check the CPU if properly installed.

• Call ASUS technical support for
assistance. See the “ASUS contact
information” on page x.

System failed memory test • Install 168-pin unbuffered

PC133 DIMMs into the DIMM
sockets.

• Check if the DIMMs on the DIMM
sockets are properly installed.

• Make sure that your DIMMs are
not defective.

• Refer to section “2.3 System
memory” for instruction on installing
a DIMM.

System failed VGA test • Install a PCI VGA card into one of

the PCI slots, or a 1.5V AGP card
into the AGP slot.

• Make sure that your VGA/AGP card
is not defective.

System failed due to CPU • In JumperFree mode, check your
over-clocking CPU settings in BIOS and make

sure you only set to the recom­mended settings. See section “4.4
Advanced menu.”

• In jumper mode, refer to section
“2.7 Switches and jumpers.”

3-2

Chapter 3: Powering up

POST Message Action

No keyboard detected • Check your keyboard if properly

connected to the purple PS/2
connector on the rear panel.

• See section “1.3.1 Identifying the
motherboard components” for the
location of the connector.

No floppy disk detected • Make sure you have connected a

floppy disk to the floppy disk
connector on the motherboard.

• See section “2.8 Connectors.”

No IDE hard disk detected • Make sure you have connected an

IDE hard disk drive to the one of the
IDE connectors on the motherboard.

• See section “2.8 Connectors.”

CPU temperature too high • Check CPU fan if working properly.
CPU fan failed • Check the CPU fan and make sure

it turns on after you applied power
to the system.

CPU voltage out of range • Check your power supply and

make sure it is not defective.

• Call ASUS technical support for
assistance. See the “ASUS contact
information” on page x.

System completed Power-On Self Test • No action required
Computer now booting from operating • No action required

system

You may disable the ASUS POST Reporter in the BIOS setup. See
section “4.4.2 I/O Device Configuration”.

ASUS P4B-LS motherboard user guide

3-3

3.3 Powering off the computer

You must first exit the operating system and shut down the system before
switching off the power. For ATX power supplies, you can press the ATX
power switch after exiting or shutting down the operating system. If you
use Windows 95/98/2000/XP, click the Start button, click Shut Down, then
click the OK button to shut down the computer. The power supply should
turn off after Windows shuts down.

The message “You can now safely turn off your computer” does not
appear when shutting down with ATX power supplies.

3-4

Chapter 3: Powering up

Chapter 4

This chapter tells how to change system
settings through the BIOS Setup menus.
Detailed descriptions of the BIOS
parameters are also provided.

BIOS setup

ASUS P4B-LS motherboard

4.1 Managing and updating your BIOS

4.1.1 Using the computer system for the first time

It is recommended that you save a copy of the original motherboard BIOS
along with a Flash Memory Writer utility (AFLASH.EXE) to a bootable
floppy disk in case you need to reinstall the BIOS later. AFLASH.EXE is a
Flash Memory Writer utility that updates the BIOS by uploading a new
BIOS file to the programmable flash ROM on the motherboard. This file
works only in DOS mode. To determine the BIOS version of your
motherboard, check the last four numbers of the code displayed on the
upper left-hand corner of your screen during bootup. Larger numbers
represent a newer BIOS file.

1. Type FORMAT A:/S at the DOS prompt to create a bootable system
disk. DO NOT copy AUTOEXEC.BAT and CONFIG.SYS to the disk.

2. Type COPY D:\AFLASH\AFLASH.EXE A:\ (assuming D is your
CD-ROM drive) to copy AFLASH.EXE to the boot disk you created.

AFLASH works only in DOS mode. It does not work in the DOS prompt
within Windows, and does not work with certain memory drivers that
may be loaded when you boot from the hard drive. It is recommended
that you reboot using a floppy disk.

3. Reboot the computer from the floppy disk.

BIOS setup must specify “Floppy” as the first item in the boot
sequence.

4. In DOS mode, type A:\AFLASH <Enter> to run AFLASH.

If the word “unknown” appears after Flash Memory:, the memory chip
is either not programmable or is not supported by the ACPI BIOS and
therefore, cannot be programmed by the Flash Memory Writer utility.

ASUS P4B-LS motherboard user guide

4-1

5. Select 1. Save Current BIOS to File from the Main menu and press
<Enter>. The Save Current BIOS To File screen appears.

6. Type a filename and the path, for example, A:\XXX-XX.XXX, then
press <Enter>.

4-2

Chapter 4: BIOS Setup

4.1.2 Updating BIOS procedures

Update the BIOS only if you have problems with the motherboard and
you are sure that the new BIOS revision will solve your problems.
Careless updating may result to more problems with the motherboard!

1. Download an updated ASUS BIOS file from the Internet (WWW or
FTP) (see ASUS CONTACT INFORMATION on page x for details) and
save to the boot floppy disk you created earlier.

2. Boot from the floppy disk.

3. At the “A:\” prompt, type AFLASH and then press <Enter>.

4. At the Main Menu, type 2 then press <Enter>. The Update BIOS
Including Boot Block and ESCD screen appears.

5. Type the filename of your new BIOS and the path, for example,
A:\XXX-XX.XXX, then press <Enter>.

To cancel this operation, press <Enter>.

6. When prompted to confirm the BIOS update, press Y to start the
update.

ASUS P4B-LS motherboard user guide

4-3

7. The utility starts to program the new BIOS information into the Flash
ROM. The boot block is updated automatically only when necessary.
This minimizes the possibility of boot problems in case of update
failures. When the programming is done, the message

Successfully”

appears.

“Flashed

8. Follow the onscreen instructions to continue.

4-4

If you encounter problems while updating the new BIOS, DO NOT turn
off the system because this may cause boot problems. Just repeat the
process, and if the problem persists, load the original BIOS file you
saved to the boot disk. If the Flash Memory Writer utility is not able to
successfully update a complete BIOS file, the system may not boot. If
this happens, call the ASUS service center for support.

Chapter 4: BIOS Setup

4.2 BIOS Setup program

This motherboard supports a programmable EEPROM that you can
update using the provided utility described in section

updating your BIOS.”

Use the BIOS Setup program when you are installing a motherboard,
reconfiguring your system, or prompted to “Run Setup”. This section
explains how to configure your system using this utility.

Even if you are not prompted to use the Setup program, you may want to
change the configuration of your computer in the future. For example, you
may want to enable the security password feature or make changes to the
power management settings. This requires you to reconfigure your system
using the BIOS Setup program so that the computer can recognize these
changes and record them in the CMOS RAM of the EEPROM.

The EEPROM on the motherboard stores the Setup utility. When you start
up the computer, the system provides you with the opportunity to run this
program. Press <Delete> during the Power-On Self Test (POST) to enter
the Setup utility, otherwise, POST continues with its test routines.

“4.1 Managing and

If you wish to enter Setup after POST, restart the system by pressing
<Ctrl> + <Alt> + <Delete>, or by pressing the reset button on the system
chassis. You can also restart by turning the system off and then back on.
Do this last option only if the first two failed.

The Setup program is designed to make it as easy to use as possible. It is
a menu-driven program, which means you can scroll through the various
sub-menus and make your selections among the predetermined choices.

Because the BIOS software is constantly being updated, the following
BIOS setup screens and descriptions are for reference purposes only,
and may not exactly match what you see on your screen.

ASUS P4B-LS motherboard user guide

4-5

4.2.1 BIOS menu bar

The top of the screen has a menu bar with the following selections:
MAIN Use this menu to make changes to the basic system

configuration.

ADVANCED Use this menu to enable and make changes to the

advanced features.

POWER Use this menu to configure and enable Power Management

features.

BOOT Use this menu to configure the default system device used

to locate and load the Operating System.

EXIT Use this menu to exit the current menu or to exit the Setup

program.

To access the menu bar items, press the right or left arrow key on the
keyboard until the desired item is highlighted.

4.2.2 Legend bar

At the bottom of the Setup screen is a legend bar. The keys in the legend
bar allow you to navigate through the various setup menus. The following
table lists the keys found in the legend bar with their corresponding
functions.

Navigation Key(s) Function Description

<F1> or <Alt + H> Displays the General Help screen from any-

where in the BIOS Setup

<Esc> Jumps to the Exit menu or returns to the main

menu from a sub-menu

Left or Right arrow Selects the menu item to the left or right
Up or Down arrow Moves the highlight up or down between fields

- (minus key) Scrolls backward through the values for the

highlighted field

+ (plus key) or spacebar Scrolls forward through the values for the high-

lighted field

<Enter> Brings up a selection menu for the highlighted

field

<Home> or <PgUp> Moves the cursor to the first field
<End> or <PgDn> Moves the cursor to the last field
<F5> Resets the current screen to its Setup Defaults
<F10> Saves changes and exits Setup

4-6

Chapter 4: BIOS Setup

General help

In addition to the Item Specific Help window, the BIOS setup program also
provides a General Help screen. You may launch this screen from any
menu by simply pressing <F1> or the <Alt> + <H> combination. The
General Help screen lists the legend keys and their corresponding
functions.

Saving changes and exiting the Setup program

See

“4.7 Exit Menu”

the setup program.

for detailed information on saving changes and exiting

Scroll bar

When a scroll bar appears to the right of a help window, it indicates that
there is more information to be displayed that will not fit in the window. Use
<PgUp> and <PgDn> or the up and down arrow keys to scroll through the
entire help document. Press <Home> to display the first page, press
<End> to go to the last page. To exit the help window, press <Enter> or
<Esc>.

Sub-menu

Note that a right pointer symbol (as shown on the
left) appears to the left of certain fields. This pointer
indicates that you can display a sub-menu from this
field. A sub-menu contains additional options for a
field parameter. To display a sub-menu, move the
highlight to the field and press <Enter>. The sub­menu appears. Use the legend keys to enter values
and move from field to field within a sub-menu as
you would within a menu. Use the <Esc> key to
return to the main menu.

Take some time to familiarize yourself with the legend keys and their
corresponding functions. Practice navigating through the various menus
and sub-menus. If you accidentally make unwanted changes to any of the
fields, use the set default hot key <F5> to load the Setup default values.
While moving around through the Setup program, note that explanations
appear in the Item Specific Help window located to the right of each menu.
This window displays the help text for the currently highlighted field.

ASUS P4B-LS motherboard user guide

4-7

4.3 Main Menu

When you enter the Setup program, the following screen appears.

System Time [XX:XX:XX]

Sets the system to the time that you specify (usually the current time). The
format is hour, minute, second. Valid values for hour, minute and second
are Hour: (00 to 23), Minute: (00 to 59), Second: (00 to 59). Use the <Tab>
or <Shift> + <Tab> keys to move between the hour, minute, and second
fields.

System Date [XX/XX/XXXX]

Sets the system to the date that you specify (usually the current date). The
format is month, day, year. Valid values for month, day, and year are
Month: (1 to 12), Day: (1 to 31), Year: (up to 2084). Use the <Tab> or
<Shift> + <Tab> keys to move between the month, day, and year fields.

Legacy Diskette A [1.44M, 3.5 in.]

Sets the type of floppy drive installed. Configuration options: [None] [360K,

5.25 in.] [1.2M , 5.25 in.] [720K , 3.5 in.] [1.44M, 3.5 in.] [2.88M, 3.5 in.]

Floppy 3 Mode Support [Disabled]

This is required to support older Japanese floppy drives. The Floppy 3
Mode feature allows reading and writing of 1.2MB (as opposed to 1.44MB)
on a 3.5-inch diskette. Configuration options: [Disabled] [Enabled]

4-8

Chapter 4: BIOS Setup

4.3.1 Primary and Secondary Master/Slave

Type [Auto]

Select [Auto] to automatically detect an IDE hard disk drive. If automatic
detection is successful, Setup automatically fills in the correct values for
the remaining fields on this sub-menu. If automatic detection fails, this may
be because the hard disk drive is too old or too new. If the hard disk was
already formatted on an older system, Setup may detect incorrect
parameters. In these cases, select [User Type HDD] to manually enter the
IDE hard disk drive parameters. Refer to the next section for details.

Before attempting to configure a hard disk drive, make sure you have
the correct configuration information supplied by the drive
manufacturer. Incorrect settings may cause the system to fail to
recognize the installed hard disk.

ASUS P4B-LS motherboard user guide

4-9

[User Type HDD]

Manually enter the number of cylinders, heads and sectors per track for
the drive. Refer to the drive documentation or on the drive label for this
information.

After entering the IDE hard disk drive information into BIOS, use a disk
utility, such as FDISK, to partition and format new IDE hard disk drives.
This is necessary so that you can write or read data from the hard disk.
Make sure to set the partition of the Primary IDE hard disk drives to
active.

If no drive is installed or if you are removing a drive and not replacing it,
select [None].

Other options for the Type field are:

[CD-ROM] - for IDE CD-ROM drives
[LS-120] - for LS-120 compatible floppy disk drives
[ZIP] - for ZIP-compatible disk drives
[MO] - for IDE magneto optical disk drives
[Other A TAPI Device] - for IDE devices not listed here

After making your selections on this sub-menu, press the <Esc> key to
return to the Main menu. When the Main menu appears, the hard disk
drive field displays the size for the hard disk drive that you configured.

4-10

Chapter 4: BIOS Setup

Translation Method [LBA]

Select the hard disk drive type in this field. When Logical Block Addressing
(LBA) is enabled, the 28-bit addressing of the hard drive is used without
regard for cylinders, heads, or sectors. Note that LBA Mode is necessary
for drives with more than 504MB storage capacity. Configuration options:
[LBA] [LARGE] [Normal] [Match Partition Table] [Manual]

Cylinders

This field configures the number of cylinders. Refer to the drive
documentation to determine the correct value. To make changes to this
field, set the Type field to [User Type HDD] and the Translation Method
field to [Manual].

Head

This field configures the number of read/write heads. Refer to the drive
documentation to determine the correct value. To make changes to this
field, set the Type field to [User Type HDD] and the Translation Method
field to [Manual].

Sector

This field configures the number of sectors per track. Refer to the drive
documentation to determine the correct value. To make changes to this
field, set the Type field to [User Type HDD] and the Translation Method
field to [Manual].

CHS Capacity

This field shows the drive’s maximum CHS capacity as calculated by the
BIOS based on the drive information you entered.

Maximum LBA Capacity

This field shows the drive’s maximum LBA capacity as calculated by the
BIOS based on the drive information you entered.

Multi-Sector Transfers [Maximum]

This option automatically sets the number of sectors per block to the
highest number that the drive supports. Note that when this field is
automatically configured, the set value may not always be the fastest
value for the drive. You may also manually configure this field. Refer to the
documentation that came with the hard drive to determine the optimum
value and set it manually. To make changes to this field, set the Type field
to [User Type HDD]. Configuration options: [Disabled] [2 Sectors] [4
Sectors] [8 Sectors] [16 Sectors] [32 Sectors] [Maximum]

ASUS P4B-LS motherboard user guide

4-11

SMART Monitoring [Disabled]

This field allows you to enable or disable the S.M.A.R.T. (Self-Monitoring,
Analysis and Reporting Technology) system that utilizes internal hard disk
drive monitoring technology. This parameter is normally disabled because
the resources used in the SMART monitoring feature may decrease
system performance. Configuration options: [Disabled] [Enabled]

PIO Mode [4]

This option lets you set a PIO (Programmed Input/Output) mode for the
IDE device. Modes 0 through 4 provide successive increase in
performance. Configuration options: [0] [1] [2] [3] [4]

Ultra DMA Mode [Disabled]

Ultra DMA capability allows improved transfer speeds and data integrity for
compatible IDE devices. Set to [Disabled] to suppress Ultra DMA
capability. To make changes to this field, set the Type field to [User Type
HDD]. Configuration options: [0] [1] [2] [3] [4] [5] [Disabled]

4-12

Chapter 4: BIOS Setup

4.3.2 Keyboard Features

Boot Up NumLock Status [On]

This field enables users to activate the Number Lock function upon system
boot. Configuration options: [Off] [On]

Keyboard Auto-Repeat Rate [6/Sec]

This controls the speed at which the system registers repeated keystrokes.
Options range from 6 to 30 characters per second. Configuration options:
[6/Sec] [8/Sec] [10/Sec] [12/Sec] [15/Sec] [20/Sec] [24/Sec] [30/Sec]

Keyboard Auto-Repeat Delay [1/4 Sec]

This field sets the time interval for displaying the first and second
characters. Configuration options: [1/4 Sec] [1/2 Sec] [3/4 Sec] [1 Sec]

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Main menu items continued...

Language [English]

This field displays the BIOS language version.

Supervisor Password [Disabled] / User Password [Disabled]

These fields allow you to set passwords. To set a password, highlight the
appropriate field and press <Enter>. Type in a password then press
<Enter>. You can type up to eight alphanumeric characters. Symbols and
other characters are ignored. To confirm the password, type the password
again and press <Enter>. The password is now set to [Enabled]. This
password allows full access to the BIOS Setup menus. To clear the
password, highlight this field and press <Enter>. The same dialog box as
above appears. Press <Enter>. The password is set to [Disabled].

A note about passwords

The BIOS Setup program allows you to specify passwords in the Main
menu. The passwords control access to the BIOS during system
startup. Passwords are not case sensitive, meaning, passwords typed
in either uppercase or lowercase letters are accepted. The BIOS Setup
program allows you to specify two different passwords: a Supervisor
password and a User password. If you did not set a Supervisor
password, anyone can access the BIOS Setup program. If you did, the
Supervisor password is required to enter the BIOS Setup program and
to gain full access to the configuration fields.

Forgot the password?

If you forget your password, you can clear it by erasing the CMOS
Real Time Clock (RTC) RAM. The RAM data containing the password
information is powered by the onboard button cell battery. See section
“2.7 Switches and jumpers” for information on how to erase the RTC
RAM.

Halt On [All Errors]

This field specifies the types of errors that will cause the system to halt.
Configuration options: [All Errors] [No Error] [All but Keyboard] [All but
Disk] [All but Disk/Keyboard]

Installed Memory [XXX MB]

This field automatically displays the amount of conventional memory
detected by the system during the boot process.

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Chapter 4: BIOS Setup

4.4 Advanced Menu

CPU Speed [Manual]

When the motherboard is set to JumperFree™ mode, this field allows you
to select the internal frequency of the CPU. Select [Manual] if you want to
make changes to the two subsequent fields. Note that selecting a
frequency higher than the CPU manufacturer recommends may cause the
system to hang or crash.

CPU Frequency Multiple (when CPU Speed is set to [Manual])

This field is for unlocked processors only. If your processor frequency
multiple is locked, you cannot access this field. This field sets the
frequency multiple between the CPU’s internal frequency (CPU speed)
and external frequency. Set this field in conjunction with CPU Frequency
(MHz) to match the speed of the CPU.

CPU Frequency (MHz) (when CPU Speed is set to [Manual])

This feature tells the clock generator what frequency to send to the system
bus and PCI bus. The bus frequency (external frequency) multiplied by the
bus multiple equals the CPU speed.

CPU/Memory Frequency Ratio [Auto]

This field determines whether the memory clock frequency is set to be in
synchronous or asynchronous mode with respect to the system frequency.
The options that appear in the popup menu vary according to the CPU
Frequency (MHz). Configuration options: [Auto] [1:1] [3:4]

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CPU VCore Setting [Auto]

The [Manual] setting allows you to manually select the core voltage
supplied to the CPU (see next item). However, it is recommended that you
keep the default setting [Auto] to allow the system to automatically
determine the appropriate CPU core voltage.

CPU VCore [1.750V]

When the CPU VCore Setting parameter above is set to [Manual], the
CPU VCore item allows you to select a specific CPU core voltage. This
field is not accessible when the CPU VCore Setting is set to [Auto].

Depending on the OVER_VOLT jumper setting (see page 2-23 for the
jumper location and settings), the CPU core voltage options vary for both
Willamette and Northwood processors. See the following table.

Refer to the CPU documentation before setting this field. A very high
core voltage may severely damage the CPU.

OVER_VOL T

P4 Processor

Jumper

Disabled Enabled

Willamette 1.750V, 1.775V, 1.800V, 1.750V, 1.775V, 1.800V,

1.825V, 1.850V 1.825V, 1.850V, 1.875V,

1.900V, 1.925V, 1.950V,

1.975V, 2.000V, 2.025V,

2.050V, 2.075V, 2.100V

Northwood 1.475V, 1.500V, 1.525V, 1.475V, 1.500V, 1.525V,

1.550V, 1.575V, 1.600V, 1.550V, 1.575V, 1.600V,

1.625V, 1.650V, 1.675V 1.625V, 1,650V, 1.675V,

1.700V, 1.725V, 1.750V

Motherboard versions earlier than R1.05 do not have the OVER_VOLT
jumper. For these motherboards, the CPU VCore configuration options
are the same as those under the Disabled column in the table.

CPU Level 1 Cache, CPU Level 2 Cache [Enabled]

These fields allow you to choose from the default of [Enabled] or choose
[Disabled] to turn on or off the CPU Level 1 and Level 2 built-in cache.
Configuration options: [Disabled] [Enabled]

BIOS Update [Enabled]

This field functions as an update loader integrated into the BIOS to supply
the processor with the required data. When set to [Enabled], the BIOS
loads the update on all processors during system bootup. Configuration
options: [Disabled] [Enabled]

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Chapter 4: BIOS Setup

PS/2 Mouse Function Control [Auto]

The default setting [Auto] allows the system to detect a PS/2 mouse at
startup. If a mouse is detected, the BIOS assigns IRQ12 to the PS/2
mouse. Otherwise, IRQ12 can be used for expansion cards. When you set
this field to [Enabled], BIOS reserves IRQ12, whether or not a PS/2 mouse
is detected at startup. Configuration options: [Enabled] [Auto]

USB Legacy Support [Auto]

This motherboard supports Universal Serial Bus (USB) devices. The
default of [Auto] allows the system to detect a USB device at startup. If
detected, the USB controller legacy mode is enabled. If not detected, the
USB controller legacy mode is disabled.

When you set this field to [Disabled], the USB controller legacy mode is
disabled whether or not you are using a USB device. Configuration
options: [Disabled] [Enabled] [Auto]

OS/2 Onboard Memory > 64M [Disabled]

When using OS/2 operating systems with installed DRAM of greater than
64MB, you need to set this option to [Enabled]. Otherwise, leave to the
default setting [Disabled]. Configuration options: [Disabled] [Enabled]

4.4.1 Chip Configuration

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SDRAM Configuration [By SPD]

This parameter allows you to set the optimal timings for items 2–5,
depending on the memory modules that you are using. The default setting
is [By SPD], which configures items 2–5 by reading the contents in the
SPD (Serial Presence Detect) device. The EEPROM on the memory
module stores critical information about the module, such as memory type,
size, speed, voltage interface, and module banks.
Configuration options: [User Defined] [By SPD]

SDRAM CAS Latency [3T]

This item controls the latency between the SDRAM read command and
the time the data actually becomes available.

The SDRAM CAS Latency parameter appears only when you set the
SDRAM Configuration to [User Defined].

SDRAM RAS to CAS Delay [3T]

This item controls the latency between the SDRAM active command and
the read/write command.

The SDRAM RAS to CAS Delay parameter appears only when you set
the SDRAM Configuration to [User Defined].

SDRAM RAS Precharge Delay [3T]

This item controls the idle clocks after issuing a precharge command to
the SDRAM.

The SDRAM RAS Precharge Delay parameter appears only when you
set the SDRAM Configuration to [User Defined].

SDRAM Active Precharge Delay [6T]

This item controls the number os SDRAM clocks used for SDRAM
parameters.

The SDRAM Active Precharge Delay parameter appears only when
you set the SDRAM Configuration to [User Defined].

SDRAM Idle Timer [Infinite]

Configuration options: [Infinite] [0T] [8T] [16T] [64T]

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Chapter 4: BIOS Setup

Optimization Mode [Normal]

This parameter allows you to enhance system performance when set to
[Turbo 1] or [Turbo 2]. If you encounter any problems with the turbo
settings, return to the default setting [Normal]. Configuration options:
[Normal] [Turbo 1] [Turbo 2]

Graphics Aperture Size [64MB]

This feature allows you to select the size of mapped memory for AGP
graphic data. Configuration options: [4MB] [8MB] [16MB] [32MB] [64MB]
[128MB] [256MB]

AGP Capability [4X Mode]

This motherboard supports the AGP 4X interface that transfers video data
at 1066MB/s. AGP 4X is backward-compatible, so you may keep the
default [4X Mode] even if you are using an AGP 1X video card. When set
to [1X Mode], the AGP interface only provides a peak data throughput of
266MB/s even if you are using an AGP 4x card.
Configuration options: [1X Mode] [4X Mode]

Video Memory Cache Mode [UC]

USWC (uncacheable, speculative write combining) is a new cache
technology for the video memory of the processor. It can greatly improve
the display speed by caching the display data. You must set this to UC
(uncacheable) if your display card does not support this feature, otherwise
the system may not boot. Configuration options: [UC] [USWC]

Memory Hole At 15M-16M [Disabled]

This field allows you to reserve an address space for ISA expansion cards.
Setting the address space to a particular setting makes that memory
space unavailable to other system components. Expansion cards can only
access memory up to 16MB. Configuration options: [Disabled] [Enabled]

Delayed Transaction [Disabled]

When set to [Enabled], this feature frees the PCI bus when the CPU is
accessing 8-bit ISA cards. This process normally consumes about 50-60
PCI clocks without PCI delayed transaction. Set this field to [Disabled]
when using ISA cards that are not PCI 2.1 compliant. Configuration
options: [Enabled] [Disabled]

Onboard PCI IDE [Both]

This field allows you to enable either the primary IDE channel or
secondary IDE channel, or both. You can also set both channels to
[Disabled]. Configuration options: [Both] [Primary] [Secondary] [Disabled]

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4.4.2 I/O Device Configuration

(Scroll down to see the last item as shown)

Floppy Disk Access Control [R/W]

When set to [Read Only], this parameter protects files from being copied to
floppy disks by allowing reads from, but not writes to, the floppy disk drive.
The default setting [R/W] allows both reads and writes. Configuration
options: [R/W] [Read Only]

Onboard Serial Port 1 [3F8H/IRQ4]
Onboard Serial Port 2 [2F8H/IRQ3]

These fields allow you to set the addresses for the onboard serial
connectors. Serial Port 1 and Serial Port 2 must have different addresses.
Configuration options: [3F8H/IRQ4] [2F8H/IRQ3] [3E8H/IRQ4] [2E8H/
IRQ10] [Disabled]

UART2 Use As [COM Port]

This field allows you to select the device on which to assign UART2.
Configuration options: [COM Port] [IR] [Smart Card Reader]

Onboard Parallel Port [378H/IRQ7]

This field sets the address of the onboard parallel port connector. If you
disable this field, the Parallel Port Mode and ECP DMA Select
configurations are not available. Configuration options: [Disabled] [378H/
IRQ7] [278H/IRQ5]

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Chapter 4: BIOS Setup

Parallel Port Mode [ECP+EPP]

This field allows you to set the operation mode of the parallel port.
[Normal] allows normal-speed operation but in one direction only; [EPP]
allows bidirectional parallel port operation; [ECP] allows the parallel port to
operate in bidirectional DMA mode; [ECP+EPP] allows normal speed
operation in a two-way mode. Configuration options: [Normal] [EPP] [ECP]
[ECP+EPP]

ECP DMA Select [3]

This field allows you to configure the parallel port DMA channel for the
selected ECP mode. This selection is available only if you select [ECP] or
[ECP+EPP] in Parallel Port Mode above. Configuration options: [1] [3]

Onboard Game Port [200H-207H]

This field allows you to select the I/O address for the game port.
Configuration options: [Disabled] [200H-207H] [208H-20FH]

Onboard MIDI I/O [Disabled]

This field allows you to select the I/O address for the game port.
Configuration options: [Disabled] [330H-331H] [300H-301H]

Onboard Card Reader Type [Disabled]

This field allows you to select the appropriate card reader type to match
your device if you installed one. Keep the default setting [Disabled] if you
did not install any. Configuration options: [Disabled] [Memory Stick]
[Secure Digital]

Onboard AC97 Audio Controller [Auto]
Onboard AC97 Modem Controller [Auto]

[Auto] allows the BIOS to detect whether you are using any modem/audio
device. If a modem/audio device is detected, the onboard modem/audio
controller is enabled; if no modem/audio device is detected, the controller
is disabled. If there are conflicts with the onboard modem/audio controller,
set the appropriate field to [Disabled]. Configuration options: [Disabled]
[Auto]

Speech POST Reporter [Enabled]

This field enables or disables the ASUS POST Reporter™ feature. See
section “1.4 Special Features” and “3.2 Vocal POST messages” for more
information. Configuration options: [Disabled] [Enabled]

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4.4.3 PCI Configuration

Slot 1, Slot 2, Slot 3, Slot 4, Slot 6 IRQ [Auto]

These fields automatically assign the IRQ for each PCI slot. The default
setting for each field is [Auto], which utilizes auto-routing to determine IRQ
assignments. Configuration options: [Auto] [NA] [3] [4] [5] [7] [9] [10] [11]
[12] [14] [15]

PCI/VGA Palette Snoop [Disabled]

Some non-standard VGA cards, like graphics accelerators or MPEG video
cards, may not show colors properly. Setting this field to [Enabled] corrects
this problem. If you are using standard VGA cards, leave this field to the
default setting [Disabled]. Configuration options: [Disabled] [Enabled]

PCI Latency Timer [32]

Leave this field to the default setting [32] for best performance and
stability.

USB Function [Both]

This motherboard supports Universal Serial Bus (USB) devices. Set this
field to [Primary] or [Both] if you want to connect USB devices.
Configuration options: [Disabled] [Primary] [Both]]

Primary VGA BIOS [PCI VGA Card]

This field allows you to select the primary graphics card. Configuration
options: [PCI VGA Card] [AGP VGA Card]

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Chapter 4: BIOS Setup

Onboard LAN Boot ROM [Disabled]

This field allows you to enable or disable the boot ROM on the onboard
LAN chipset. Set this field to [Enabled] if you wish to use the onboard LAN
boot ROM. Configuration options: [Disabled] [Enabled]

ONB SCSI BIOS First [No]

When set to [Yes], this field allows the onboard SCSI BIOS to start up
before the PCI devices. When set to [No], the onboard SCSI BIOS starts
up after the PCI devices have been initialized.
Configuration options: [No] [Yes]

4.4.3.1 PCI IRQ Resource Exclusion

IRQ XX Reserved [No/ICU]

These fields indicate whether or not the displayed IRQ for each field is
being used by a legacy (non-PnP) ISA card. The setting [No/ICU] for an
IRQ field indicates that you are using the ISA Configuration Utility (ICU),
and that this particular IRQ is NOT required by a legacy ISA card. Set the
IRQ field to [Yes] if you install a legacy ISA card that requires a unique IRQ
and you are NOT using ICU. Configuration options: [No/ICU] [Yes]

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4.5 Power Menu

The Power menu allows you to reduce power consumption. This feature
turns off the video display and shuts down the hard disk after a period of
inactivity.

Power Management [User Defined]

This field allows you to activate or deactivate the automatic power saving
features. When set to [Disabled], the power management features do not
function regardless of the other settings on this menu. The [User Defined]
option allows you to set the period of inactivity before the system enters
suspend mode. Refer to “Suspend Mode” later in this section.

When set to [Max Saving], system power is conserved to its greatest
amount. This setting automatically puts the system into suspend mode
after a brief period of system inactivity. [Min Saving] allows the least power
saving as the system enters suspend mode only after a long period of
inactivity. Configuration options: [User Defined] [Disabled] [Min Saving]
[Max Saving]

You should install the Advanced Power Management (APM) utility to
keep the system time updated even when the computer enters
suspend mode. In Windows 3.x and Windows 95, you need to install
Windows with the APM feature. In Windows 98 or later, APM is
automatically installed as indicated by a battery and power cord icon
labeled “Power Management” in the Control Panel. Select the item
“Advanced” in the Power Management Properties dialog box.

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Chapter 4: BIOS Setup

Video Off Option [Suspend -> Off ]

This field determines when to activate the video off feature for monitor
power management. Configuration options: [Always On] [Suspend -> Off]

Video Off Method [DPMS OFF]

This field defines the video off features. The Display Power Management
System (DPMS) feature allows the BIOS to control the video display card if
it supports the DPMS feature. [Blank Screen] only blanks the screen. Use
this for monitors without power management or “green” features.

Even if installed, your screen saver does not display when you select
[Blank Screen] for the above field.

[V/H SYNC+Blank] blanks the screen and turns off vertical and horizontal
scanning. Configuration options: [Blank Screen] [V/H SYNC+Blank]
[DPMS Standby] [DPMS Suspend] [DPMS OFF] [DPMS Reduce ON]

HDD Power Down [Disabled]

Shuts down any IDE hard disk drives in the system after a period of
inactivity as set in this user-configurable field. This feature does not affect
SCSI hard drives. Configuration options: [Disabled] [1 Min] [2 Min] [3
Min]...[15 Min]

ACPI Suspend To RAM [Disabled]

This field allows you to enable or disable the ACPI Suspend-to-RAM
feature. To support this feature, the +5VSB of the power supply should
have the capacity to provide more than 720mA current. Configuration
options: [Disabled] [Enabled]

Suspend Mode [Disabled]

Sets the time period before the system goes into suspend mode.
Configuration options: [Disabled] [1~2 Min] [2~3 Min] [4~5 min] [8~9 Min]
[20 Min] [30 Min]

PWR Button < 4 Secs [Soft Off]

When set to [Soft off], the ATX switch can be used as a normal system
power-off button when pressed for less than 4 seconds. [Suspend] allows
the button to have a dual function where pressing less than 4 seconds
puts the system in sleep mode. Regardless of the setting, holding the ATX
switch for more than 4 seconds powers off the system. Configuration
options: [Soft off] [Suspend]

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4.5.1 Power Up Control

AC PWR Loss Restart [Disabled]

This allows you to set whether or not to reboot the system after power
interruptions. [Disabled] leaves your system off while [Enabled] reboots the
system. [Previous State] sets the system back to the state it was before
the power interruption. Configuration options: [Disabled] [Enabled]
[Previous State]

Wake/Power Up On Ext. Modem [Disabled]

This allows either settings of [Enabled] or [Disabled] for powering up the
computer when the external modem receives a call while the computer is
in Soft-off mode. Configuration options: [Disabled] [Enabled]

The computer cannot receive or transmit data until the computer and
applications are fully running. Thus, connection cannot be made on the
first try. Turning an external modem off and then back on while the
computer is off causes an initialization string that turns the system
power on.

Power Up On PCI Card [Disabled]

When set to [Enabled], this parameter allows you to turn on the system
through a PCI modem. This feature requires an ATX power supply that
provides at least 1A on the +5VSB lead. Configuration options: [Disabled]
[Enabled]

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Chapter 4: BIOS Setup

Power Up On USB [Disabled]

When set to [Enabled], this field allows system power up through a USB
device activity. This feature requires an ATX power supply that provides at
least 1A on the +5VSB lead. Configuration options: [Disabled] [Enabled]

Power On By PS/2 Keyboard [Space Bar]

This parameter allows you to use specific keys on the keyboard to turn on
the system. This feature requires an ATX power supply that provides at
least 1A on the +5VSB lead. Configuration options: [Disabled] [Space Bar]
[Ctrl-Esc] [Power Key]

Power On By PS/2 Mouse [Disabled]

When set to [Enabled], this parameter allows you to use the PS/2 mouse
to turn on the system. This feature requires an ATX power supply that
provides at least 1A on the +5VSB lead. Configuration options: [Disabled]
[Enabled]

Automatic Power Up [Disabled]

This allows an unattended or automatic system power up. You may
configure your system to power up at a certain time of the day by selecting
[Everyday] or at a certain time and day by selecting [By Date].
Configuration options: [Disabled] [Everyday] [By Date]

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4.5.2 Hardware Monitor

MB Temperature [xxxC/xxxF]
CPU Temperature [xxxC/xxxF]

The onboard hardware monitor automatically detects the MB
(motherboard) and CPU temperatures.

CPU Fan Speed [xxxxRPM]
Power Fan Speed
Chassis Fan Speed [N/A]

The onboard hardware monitor automatically detects the CPU and chassis
fan speeds in rotations per minute (RPM).

VCORE Voltage, +3.3V Voltage, +5V Voltage, +12V Voltage

The onboard hardware monitor automatically detects the voltage output
through the onboard voltage regulators.

If any of the monitored items is out of range, the following error
message appears: “Hardware Monitor found an error. Enter Power
setup menu for details”. You will then be prompted to “Press F1 to
continue or DEL to enter SETUP”.

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Chapter 4: BIOS Setup

4.6 Boot Menu

Boot Sequence

The Boot menu allows you to select among the four possible types of boot
devices listed using the up and down arrow keys. By using the <+> or
<Space> key, you can promote devices and by using the <-> key, you can
demote devices. Promotion or demotion of devices alters the priority which
the system uses to search for a boot device on system power up.
Configuration fields include Removable Devices, IDE Hard Drive, ATAPI
CD-ROM, and Other Boot Device.

Removable Device [Legacy Floppy]

Configuration options: [Disabled] [Legacy Floppy] [LS-120] [ZIP]
[ATAPI MO]

IDE Hard Drive

This field allows you to select which IDE hard disk drive to use in the boot
sequence. Pressing [Enter] will show the product IDs of all connected IDE
hard disk drives.

ATAPI CD-ROM

This field allows you to select which ATAPI CD-ROM drive to use in the
boot sequence. Pressing [Enter] will show the product IDs of all your
connected ATAPI CD-ROM drives.

Other Boot Device Select [INT18 Device (Network)]

Configuration options: [Disabled] [SCSI Boot Device] [INT18 Device
(Network)]

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Plug & Play O/S [No]

This field allows you to use a Plug-and-Play (PnP) operating system to
configure the PCI bus slots instead of using the BIOS. When [Yes] is
selected, interrupts may be reassigned by the OS. If you installed a non­PnP OS or if you want to prevent reassigning of interrupt settings, keep
the default setting [No]. Configuration options: [No] [Yes]

Reset Configuration Data [No]

The Extended System Configuration Data (ESCD) contain information
about non-PnP devices. It also holds the complete record of how the
system was configured the last time is was booted. Select [Yes] if you
want to clear these data during the Power-On-Self-Test (POST).
Configuration options: [Disabled] [Enabled]

Boot Virus Detection [Enabled]

This field allows you to set boot virus detection, ensuring a virus-free boot
sector. The system halts and displays a warning message when it detects
a virus. If this occurs, you can either allow the operation to continue or use
a virus-free bootable floppy disk to restart and investigate your system.
Configuration options: [Disabled] [Enabled]

Quick Power On Self Test [Enabled]

This field speeds up the Power-On-Self Test (POST) routine by skipping
retesting a second, third, and fourth time. Configuration options: [Disabled]
[Enabled]

Boot Up Floppy Seek [Enabled]

When enabled, the BIOS will seek the floppy disk drive to determine
whether the drive has 40 or 80 tracks. Configuration options: [Disabled]
[Enabled]

Full Screen Logo [Enabled]

This allows you to enable or disable the full screen logo display feature.
Configuration options: [Disabled] [Enabled]

Make sure that the above item is set to [Enabled] if you wish to use the
ASUS MyLogo™ feature.

Interrupt Mode [APIC]

The Advanced Programmable Interrupt Controller (APIC) setting allows
you to distribute interrupt routings other than the 16 IRQs. The
Programmable Interrupt Controller (PIC) setting allows you to use the 16
IRQs only. Configuration options: [PIC] [APIC]

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Chapter 4: BIOS Setup

4.7 Exit Menu

When you have made all of your selections from the various menus in the
Setup program, save your changes and exit Setup. Select Exit from the
menu bar to display the following menu.

Pressing <Esc> does not immediately exit this menu. Select one of the
options from this menu or <F10> from the legend bar to exit.

Exit Saving Changes

Once you are finished making your selections, choose this option from the
Exit menu to ensure the values you selected are saved to the CMOS RAM.
The CMOS RAM is sustained by an onboard backup battery and stays on
even when the PC is turned off. When you select this option, a
confirmation window appears. Select [Yes] to save changes and exit.

If you attempt to exit the Setup program without saving your changes,
the program prompts you with a message asking if you want to save
your changes before exiting. Pressing <Enter> saves the changes
while exiting.

Exit Discarding Changes

Select this option only if you do not want to save the changes that you
made to the Setup program. If you made changes to fields other than
system date, system time, and password, the BIOS asks for a confirmation
before exiting.

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Load Setup Defaults

This option allows you to load the default values for each of the
parameters on the Setup menus. When you select this option or if you
press <F5>, a confirmation window appears. Select [Yes] to load default
values. Select Exit Saving Changes or make other changes before saving
the values to the non-volatile RAM.

Discard Changes

This option allows you to discard the selections you made and restore the
previously saved values. After selecting this option, a confirmation
appears. Select [Yes] to discard any changes and load the previously
saved values.

Save Changes

This option saves your selections without exiting the Setup program. You
can then return to other menus and make further changes. After you select
this option, a confirmation window appears. Select [Yes] to save any
changes to the non-volatile RAM.

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Chapter 4: BIOS Setup

Chapter 5

This chapter describes the contents of the
support CD that comes with the
motherboard package.

Software support

ASUS P4B-LS motherboard

5.1 Install an operating system

This motherboard supports Windows 98/ME/NT/2000/XP and OS/2
operating system (OS). Always install the latest OS version and
corresponding updates so you can maximize the features of your
hardware.

5.1.1 Windows 98 first time installation

When you start Windows for the first time after installing the motherboard,
Windows 98 detects all Plug-n-Play devices devices. Follow the Add New

Hardware

restart, select No. Refer to the following sections in this chapter to install
the software and drivers contained in the support CD.

wizard to install the necessary device drivers. When prompted to

Because motherboard settings and hardware options vary, use the
setup procedures presented in this chapter for general reference only.
Refer to your OS documentation for more information.

5.2 Support CD information

The support CD that came with the motherboard contains useful software
and several utility drivers that enhance the motherboard features.

The contents of the support CD are subject to change at any time
without notice. Visit the ASUS website for updates.

5.2.1 Running the support CD

To begin using the support CD, simply insert the CD into your CD-ROM
drive. The CD automatically displays the welcome screen and the
installation menus if Autorun is enabled in your computer.

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5-1

If the welcome screen did not appear automatically, locate and double­click on the file ASSETUP.EXE from the BIN folder in the support CD to
display the menus.

5.2.2 Main menu

From the welcome screen, the program takes you directly to the main
menu. The main menu displays an image of the motherboard, and the
buttons and icons that link you to the software, drivers, utilities, and other
information contained in the support CD.

5-2

Place your mouse cursor on
an icon and click to display
the specified item

Click on a button to display
the available options

Chapter 5: Software support