ASUS P2LB User Manual

R

P2L-B

Pentium® II Motherboard

USER’S MANUAL

USER'S NOTICE

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”).

ASUS PROVIDES THIS MANUAL “AS IS” WITHOUT WARRANTY OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED T O THE IMPLIED
WARRANTIES OR CONDITIONS OF MERCHANT ABILITY 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.

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.

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.

• Intel, LANDesk, and Pentium are registered trademarks of Intel Corporation.

• IBM and OS/2 are registered trademarks of International Business Machines.

• Symbios is a registered trademark of Symbios Logic Corporation.

• Windows and MS-DOS are registered trademarks of Microsoft Corporation.

• Sound Blaster AWE32 and SB16 are trademarks of Creative Technology Ltd.

• Adobe and Acrobat are registered trademarks of Adobe Systems Incorporated.
The product name and revision number are both printed on the product itself. Manual revi-

sions are released for each product design represented by the digit before and after the period
of the manual revision number . Manual updates are represented by the third digit in the manual
revision number.

For previous or updated manuals, BIOS, drivers, or product release information, contact ASUS
at http://www.asus.com.tw or through any of the means indicated on the following page.

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 MA Y APPEAR IN THIS MANUAL, INCLUD­ING THE PRODUCTS AND SOFTWARE DESCRIBED IN IT.

Copyright © 1998 ASUSTeK COMPUTER INC. All Rights Reserved.

Product Name: ASUS P2L-B
Manual Revision: 1.02
Release Date: February 1998

2 ASUS P2L-B User’s Manual

ASUS CONTACT INFORMATION

ASUSTeK COMPUTER INC.

Marketing

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

Technical Support

Fax: [phone]
BBS: [phone]
Email: [e-mail]
WWW: www.asus.com.tw
FTP: ftp.asus.com.tw/pub/ASUS

ASUS COMPUTER INTERNATIONAL

Marketing

Address: 6737 Mowry Ave, Mowry Business Center, Building 2,

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

Technical Support

Fax: [phone]
BBS: [phone]
Email: [e-mail]
WWW: www.asus.com
FTP: ftp.asus.com.tw/pub/ASUS

ASUS COMPUTER GmbH

Marketing

Address: Harkort Str. 25, 40880 Ratingen, BRD, Germany
Telephone: [phone]
Fax: [phone]
Email: [e-mail]

Technical Support

Hotline: [phone]
BBS: 49-2102-448690
Email: [e-mail]
WWW: www.asuscom.de
FTP: ftp.asuscom.de/pub/ASUSCOM

ASUS P2L-B User’s Manual 3

CONTENTS

I. INTRODUCTION........................................................................... 7

How this manual is organized.......................................................... 7

Item Checklist .................................................................................. 7

II. FEATURES .................................................................................... 8

Features of the ASUS P2L-B Motherboard ..................................... 8

Introduction to ASUS Smart Series motherboards ............... 9

Parts of the ASUS P2L-B Motherboard........................................... 11

III. INSTALLATION .......................................................................... 12

ASUS P2L-B Motherboard Layout ................................................. 12

Installation Steps.............................................................................. 14

1. Jumpers ........................................................................................ 14

Jumper Settings .................................................................... 15

2. System Memory (DIMM) ........................................................... 17

DIMM Memory Installation ................................................. 18

3. Central Processing Unit (CPU)................................................... 19

Pentium II Processor............................................................. 19

AAVID Heatsink .................................................................. 23

Elan V ital Heatsink............................................................... 23

4. Expansion Cards .......................................................................... 24

Expansion Card Installation Procedure ................................ 24

Assigning IRQs for Expansion Cards................................... 24

Assigning DMA Channels for ISA Cards............................. 25

ISA Cards and Hardware Monitor ........................................ 25

5. External Connectors.................................................................... 26

Power Connection Procedures ................................................... 33

IV. BIOS SOFTWARE ........................................................................ 34

Support Software ............................................................................. 34

Flash Memory Writer Utility...................................................... 34

Main Menu ........................................................................... 34

Advanced Features Menu ..................................................... 35

Managing and Updating Your Motherboard’s BIOS.................. 36

6. BIOS Setup ................................................................................. 37

Load Defaults ....................................................................... 38

Standard CMOS Setup ............................................................... 38

Details of Standard CMOS Setup:........................................ 38

BIOS Features Setup .................................................................. 41

Details of BIOS Features Setup............................................ 41

Chipset Features Setup ............................................................... 44

Details of Chipset Features Setup......................................... 44

4 ASUS P2L-B User’s Manual

CONTENTS

Power Management Setup.......................................................... 47

Details of Power Management Setup ................................... 47

PNP and PCI Setup .................................................................... 50

Details of PNP and PCI Setup .............................................. 50

Load BIOS Defaults ................................................................... 52

Load Setup Defaults ................................................................... 52

Supervisor Password and User Password .................................. 53

IDE HDD Auto Detection .......................................................... 54

Save & Exit Setup ...................................................................... 55

Exit Without Saving ................................................................... 55

V. SUPPORT SOFTWARE ................................................................ 56

ASUS Smart Motherboard Support CD........................................... 56

Desktop Management Interface (DMI)............................................ 57

Introducing the ASUS DMI Configuration Utility ............... 57

System Requirements ........................................................... 57

Using the ASUS DMI Configuration Utility ........................ 58

VI. ASUS PCI SCSI Cards ................................................................ 59

Symbios SCSI BIOS and Drivers .................................................... 59

ASUS PCI-SC200 & PCI-SC860 SCSI Cards ................................ 59

Setting Up the ASUS PCI-SC200 & PCI-SC860 ....................... 60

Setting the INT Assignment for the ASUS PCI-SC200 ............. 60

Terminator Requirements for SCSI Devices .............................. 60

Terminator Settings for the ASUS PCI-SC860 .......................... 61

Terminator Settings for the ASUS PCI-SC200 .......................... 61

SCSI ID Numbers for SCSI Devices ......................................... 62

SCSI ID Priority ......................................................................... 62

VII. ASUS LAN Card......................................................................... 63

ASUS PCI-L101 Fast Ethernet Card ............................................... 63

Features ............................................................................................ 64

Software Driver Support ............................................................ 64

Question and Answer ................................................................. 64

ASUS P2L-B User’s Manual 5

FCC & DOC COMPLIANCE

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:

• Re-orient 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.

WARNING! 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.

6 ASUS P2L-B User’s Manual

I. INTRODUCTION

How this manual is organized

This manual is divided into the following sections:

I. Introduction: Manual information and checklist
II. Features: Information and specifications concerning this product
III. Installation: Instructions on setting up the motherboard
IV. BIOS Software: Instructions on setting up the BIOS software
V. Support Software: Information on the included support software
VI. ASUS SCSI Cards: Installation of ASUS SCSI cards (optional)
VII. ASUS L101 Card: Installation of the ASUS LAN card (optional)

Item Checklist

Please check that your package is complete. If you discover damaged or missing
items, please contact your retailer.

(1) ASUS Motherboard

I. INTRODUCTION

(Sections/Checklist)

(1) Retention mechanism & heatsink support
(2) Attach mount bridges (factory installed)
(1) 9pin male serial + 25pin male serial external connector set
(1) 25pin female parallel + 6pin female PS/2 mouse external connector set
(1) IDE ribbon cable for master and slave drives
(1) Floppy ribbon cable for (1) 5.25inch floppy and (2) 3.5inch floppies
(1) bag of spare jumpers
(1) diskette or CD with support drivers and utilities:

• Flash Memory Writer utility to update the onboard programmable BIOS

• LANDesk Client Manager (LDCM) Software

• ASUS PC Probe Utility

• Desktop Management Interface (DMI) utility

• Readme files for descriptions and use of the files

• Technical Support Form
(1) User’s Manual
PS/2 Mouse, Infrared, USB1, and USB2 external connector module (optional)
ASUS PCI-SC200 Fast-SCSI or PCI-SC860 Ultra-Fast SCSI card (optional)
ASUS PCI-L101 Wake-on-LAN 10/100 Ethernet Card (optional)

ASUS P2L-B User’s Manual 7

II. FEATURES

(Features)

II. FEATURES

Features of the ASUS P2L-B Motherboard

The ASUS P2L-B is carefully designed for the demanding PC user who wants many
intelligent features in a small package. This motherboard:

• Intel Chipset: Features Intel’s 440LX AGPset with I/O subsystems.

®

• Multi-Speed: Supports an Intel Pentium

• Multi-Cache: Supports a Pentium

0KB Pipelined Burst Level 2 cache in the Single Edge Contact (SEC) cartridge.

• Versatile Memory: Is equipped with three DIMM sockets to support 8MB-

128MB 168-pin 3.3Volt SDRAM/EDO memory modules up to 384MB.

• AGP: Supports an Accelerated Graphics Port card for high performance, com-

ponent level interconnect targeted at 3D graphical display applications.

• Dual Power Supply: Has both AT and ATX power connectors onboard to sup-

port an AT or ATX power supply with soft-on/off features.

• ISA & PCI Expansion: Provides two 16-bit ISA expansion slots and three 32-

bit PCI expansion slots.

®

II processor from 233MHz–333MHz.

II processor with either 512KB, 256KB, or

• Wake on LAN: Supports Wake on LAN activity through optional ASUS

PCI-L101 Fast Ethernet card.

• Super Multi-I/O: Provides two high-speed UART compatible serial ports and

one parallel port with EPP and ECP capabilities. UART2 can also be directed
from COM2 to the Infrared Module for wireless connections.

• Desktop Management Interface (DMI): Supports DMI through BIOS which

allows hardware to communicate within a standard protocol creating a higher
level of compatibility. (Requires DMI-enabled components.) (See section V)

• PCI Bus Master IDE: Comes with an onboard PCI Bus Master IDE controller

with two connectors that supports four IDE devices in two channels, supports
PIO Modes 3 and 4 and Bus Master IDE DMA Mode 2, and supports Enhanced
IDE devices such as T ape Backup and CD-ROM drives. Supports two drives of
either 5.25-inch (360KB or 1.2MB) or 3.5-inch (720KB, 1.44MB, or 2.88MB)
disk drives. Supports Japanese “Floppy 3 mode” (3.5-inch disk drive: 1.2MB)
and LS-120 floppy disk drives (3.5-inch disk drive: 120 MB, 1.44MB, 720K).
BIOS supports IDE CD-ROM or SCSI device boot-up.

• Symbios SCSI BIOS: Supports optional ASUS SCSI controller cards through

onboard firmware.

• Easy Installation: Is equipped with BIOS that supports auto detection of hard

drives, PS/2 mouse, and Plug and Play devices to make setup of hard drives,
expansion cards, and other devices virtually automatic.

• Optional PS/2 Mouse, USB, IrDA: Supports an optional cable and bracket set

to mount the connectors to an unused expansion slot on the system chassis. A
second IrDA connector is available for a standard individual infrared cable set.

8 ASUS P2L-B User’s Manual

II. FEATURES

Introduction to ASUS Smart Series motherboards

Performance

• SDRAM Optimized Performance - ASUS smart series of motherboards sup-

port the new generation memory - Synchronous Dynamic Random Access
Memory (SDRAM) which increases the data transfer rate from 264MB/s max
using EDO memory to 528MB/s max using SDRAM.

• Double the IDE Transfer Speed - ASUS smart series of motherboards with

Intel chipsets improves IDE transfer rate using Bus Master UltraDMA/33 IDE
which can handle data transfer up to 33MB/s. The best of all is that this new
technology is compatible with existing ATA-2 IDE specs so there is no need to
upgrade current hard drives or cables.

• Concurrent PCI - Concurrent PCI allows multiple PCI transfers from PCI master

busses to memory to CPU.

(Smart Series)

II. FEATURES

• ACPI Ready - ACPI (Advanced Configuration and Power Interface) is also

implemented on all ASUS smart series of motherboards. ACPI provide more
Energy Saving Features for the future operating systems (OS) supporting OS
Direct Power Management (OSPM) functionality. With these features imple­mented in the OS, PCs can be ready around the clock everyday, yet satisfy all
the energy saving standards. To fully utilize the benefits of ACPI, an ACPI­supported OS such as in the next release of Windows 95 must be used.

• PC ’97 Compliant - Both the BIOS and hardware levels of ASUS smart series

of motherboards meet PC ’97 compliancy. The new PC 97 requirements for
systems and components are based on the following high-level goals: Support
for Plug and Play compatibility and power management for configuring and
managing all system components, and 32-bit device drivers and installation pro­cedures for both Windows 95 and Windows NT.

Intelligence: (with optional Hardware/Thermal Monitor only)

• Fan Status Monitoring and Alarm - To prevent system overheat and system

damage, the CPU fan and system fans can be monitored for RPM and failure.
Each fan can be set for its normal RPM range and alarm thresholds.

• Temperature Monitoring and Alert - To prevent system overheat and system

damage, there are heat sensors to monitor the CPU (the Pentium II processor
requires a special heatsink with a thermal sensor) and system temperatures to
warn of damaging temperatures.

ASUS P2L-B User’s Manual 9

• Voltage Monitoring and Alert - System voltage levels are monitored to ensure

• System Resources Alert - T oday’ s operating systems such as W indows 95, W in-

II. FEATURES

(TX97 Series)

• Auto Fan Off - The system fans will power off automatically even in sleep

• Dual Function Power Button (requir es ATX power supply) - The system can

II. FEATURES

stable current to critical motherboard components. Voltage specifications are
more critical for future processors, so monitoring is necessary to ensure proper
system configuration and management.

dows NT , and OS/2, require much more memory and hard drive space to present
enormous user interfaces and run large applications. The system resource moni­tor will warn the user before the system resources are used up to prevent pos­sible application crashes. Suggestions will give the user information on manag­ing their limited resources more efficiently.

mode. This function reduces both energy consumption and system noise, and
is a important feature to implement silent PC systems.

be in one of two states, one is Sleep mode and the other is the Soft-Off mode.
Pushing the power button for less than 4 seconds places the system into Sleep
mode. When the power button is pressed for more than 4 seconds, it enters the
Soft-Off mode.

• Remote Ring On (requires ATX power supply and external modem) - This

allows a computer to be turned on remotely through an external modem. With
this benefit on-hand, any user can access vital information from their computer
from anywhere in the world!

• Message LED - Chassis LEDs now act as information providers. Through the

way a particular LED illuminates, the user can determine the stage the computer
is in. A simple glimpse provides useful information to the user.

10 ASUS P2L-B User’s Manual

II. FEATURES

Parts of the ASUS P2L-B Motherboard

Hardware Monitor
2 ISA Slots

3 PCI Slots

Thermal Sensor

Super Multi-I/O

PS/2 Mouse, USB, IrDA

Serial, Parallel, Floppy

AT Power
Connector

ATX Power
Connector

AGP Slot

Intel’s 440LX
AGPset

3 DIMM Sockets

SEC CPU Socket
(Slot1)

IDE Connectors

Programmable
Flash ROM

II. FEATURES

(Motherboard Parts)

ASUS P2L-B User’s Manual 11

III. INSTALLATION

ASUS P2L-B Motherboard Layout

ISA Slot 2

(Motherboard Layout)

III. INSTALLATION

Flash EEPROM

ISA Slot 1

System BIOS

Hardware
Monitor

ASUS

ASIC

Thermal
Sensor

PCI Slot 3

Intel
PIIX4
PCIset

Primary IDE

Super

Multi-I/O

PCI Slot 2

RTC Clear

Secondary IDE

PCI Slot 1

Wake
on LAN

BIOS Power

CR2032 3V
Lithium Cell

Key­board

AT Power Input

P9

ATX Power Input

P8

Single Edge Contact CPU Slot (Slot 1)

PS/2 Mouse,
USB, IrDA

Parallel (Printer) Port

Floppy Drives

COM 1

Serial Ports

COM 2

Pentium II Thermal
Sensor Connector

R

Power Fan

RT2

Keyboard
Power

AGP Slot

Socket 2 (64-bit or 72-bit with ECC) 168-pin DIMM module

Socket 3 (64-bit or 72-bit with ECC) 168-pin DIMM module

Socket 1 (64-bit or 72-bit with ECC) 168-pin DIMM module

Intel
440LX
PCIset

CPU Fan

Infrared

Panel Connectors

Freq. Ratio

BF0
BF1
BF2
BF3

IDE LED

Chassis
Fan

Row

54

32

10

FS0
FS1
FS2

Clock Freq

12 ASUS P2L-B User’s Manual

III. INSTALLATION

Jumpers

1) CLRTC p. 15 Real Time Clock RAM (Clear Data)

2) KBPWR p. 15 Keyboard Power Up (Enable/Disable)

3) FS0, FS1, FS2 p. 16 CPU External Clock (BUS) Frequency Selection

4) BF0, BF1, BF2, BF3 p. 16 CPU:BUS Frequency Ratio

Expansion Slots

1) DIMM Sockets p. 17 168-Pin DIMM Memory Support

2) SEC CPU Slot p. 19 Single Edge Contact CPU Support

3) ISA Slot 1, 2 p. 24 16-bit ISA Bus Expansion Slots

4) PC I Slot 1 , 2 , 3 p. 24 32-bit PCI Bus Expansion Slots

5) AGP p. 25 Accelerated Graphics Port

Hardware Monitor

1) RT2 p. 22 Pentium II Processor Thermal Sensor Connector

*

Connectors

1) KB p. 26 Keyboard Connector (5-pin Female)

2) FLOPPY p. 26 Floppy Drive Connector (34-1pins)

3) PRINTER p. 27 Parallel (Printer) Port Connector (26-1pins)

4) COM1, COM2 p. 27 Serial Port COM1 & COM2 (10-1pins)

5) IDE1, IDE2 p. 28 Primary / Secondary IDE Connector (40-1pins)

6) IDELED p . 2 8 IDE LED Activity Light (2 pins)

7) FAN p. 27 Power Supply, Chassis, CPU Fan Power Leads (3 pins)

8) W0L_CON p. 32 Wake on LAN Activity Connector (3-pins)

9) MSG.LED (PANEL) p. 30 System Message LED (2 pins)

10) SMI (PANEL) p. 30 SMI Switch Lead (2 pins)

11) PWR SW. (PANEL) p. 30 ATX Power & Soft-Off Switch Lead (2 pins)

12) RESET (PANEL) p. 30 Reset Switch Lead (2 pins)

13)

PWR.LED (

14)

KEYLOCK (

15) SPEAKER (PANEL) p. 30 Speaker Output Connector (4 pins)

16) USB/MIR p. 31 PS/2 Mouse/USB/IR Combo-Connector (18-1pins)

17) IR p. 31 Second Infrared Port Module Connector (5-pins)

PANEL

PANEL

)

p. 30 System Power LED Lead (3 pins)

)

p. 30 Keyboard Lock Switch Lead (2 pins)

(Map of Board)

III. INSTALLATION

18) ATX POWER p. 32 ATX Motherboard Power Connector (20-pins)

19) AT POWER p. 32 AT Motherboard Power Connector (12-pins)

*

The onboard hardware monitor uses the address 290H-297H so legacy ISA cards

must not use this address or else conflicts will occur.

ASUS P2L-B User’s Manual 13

III. INSTALLATION

III. INSTALLATION

Installation Steps

Before using your computer, you must complete the following steps:

1. Set Jumpers on the Motherboard

2. Install System Memory Modules

3. Install the Central Processing Unit (CPU)

4. Install Expansion Cards

5. Connect Ribbon Cables, Cabinet Wires, and Power Supply

6. Setup the BIOS Software

1. Jumpers

Several hardware settings are made through the use of jumper caps to connect jumper
pins (JP) on the motherboard. See motherboard layout for locations of jumpers. The
jumper settings will be described numerically, such as [----], [1-2], [2-3] for no con-

(Jumpers)

nection, connect pins 1&2, and connect pins 2&3 respectively. Pin 1 for our mother­boards is always on top
the keyboard connector away from yourself. A “1” is written besides pin 1 on jumpers
with three pins. The jumpers will also be shown graphically such as to connect
pins 1&2 and to connect pins 2&3. Jumpers with two pins will be shown as

for Short (On) and for Open (Off). For manufacturing simplicity , the jump­ers may be sharing pins from other groups. Use the diagrams in this manual instead of
following the pin layout on the board. Settings with two jumper numbers require that
both jumpers be moved together. To connect the pins, simply place a plastic jumper
cap over the two pins as diagramed.

WARNING! Computer motherboards, baseboards and components, such as SCSI

cards, contain very delicate Integrated Circuit (IC) chips. To protect them against
damage from static electricity , you should follow some precautions whenever you
work on your computer .

1. Unplug your computer when working on the inside.

Pin 1

or on the left

Pin 1

when holding the motherboard with

2. Use a grounded wrist strap before handling computer components. If you do
not have one, touch both of your hands to a safely grounded object or to a
metal object, such as the power supply case.

3. Hold components by the edges and try not to touch the IC chips, leads or
connectors, or other components.

4. Place components on a grounded antistatic pad or on the bag that came with
the component whenever the components are separated from the system.

14 ASUS P2L-B User’s Manual

III. INSTALLATION

Jumper Settings

1. Real Time Clock (RTC) RAM (CLRTC)

The CMOS RAM is powered by the onboard button cell battery. To clear the
RTC data: (1) Unplug your computer, (2) Short solder points, (3) Turn on your
computer, (4) Hold down <Delete> during bootup and enter BIOS setup to re­enter user preferences.

RTC RAM CLRTC

Clear Data [short solder points momentarily]

R

CLRTC

P2L-B Clear RTC RAM

2. Keyboard Power Up (KBPWR)

Set this jumper to Enable if you wish to use your keyboard to power up your
system. Requires an ATX power supply that can supply at least 300mAmp on
the +5VSB lead and new BIOS support. The default is set to Disable because
your system will not function without the proper ATX power supply.

Setting KBPWR

Disable [1-2] (default)
Enable [2-3]

KBPWR

123

R

Disable

(Default)

KBPWR

123

Enable

(Jumpers)

III. INSTALLATION

P2L-B Keyboard Power Up

ASUS P2L-B User’s Manual 15

III. INSTALLATION

3. CPU External (BUS) Frequency Selection (FS0, FS1, FS2)

These jumpers tell the clock generator what frequency to send to the CPU. These
allow the selection of the CPU’ s External frequency (or BUS Clock). The BUS Clock
times the BUS Ratio equals the CPU's Internal frequency (the advertised CPU speed).

4. CPU to BUS Frequency Ratio (BF0, BF1, BF2, BF3)

These jumpers set the frequency ratio between the Internal frequency of the CPU
and the External frequency (called the BUS Clock) within the CPU. These must
be set together with the above jumpers CPU External (BUS) Frequency Selection.

III. INSTALLATION

(Jumpers)

BF0
BF1
BF2
BF3

FS0
FS1
FS2

23

1

3.5x(7/2)

123

66MHz

23

1

BF0

R

BF1
BF2
BF3

3.0x(3/1)

CPU Core:Bus Frequency Multiple

123

FS0
FS1
FS2

60MHz

CPU Bus Frequency

BF0
BF1
BF2
BF3

FS0
FS1
FS2

23

1

4.0x(4/1)

123

75MHz

BF0
BF1
BF2
BF3

FS0
FS1
FS2

23

1

4.5x(9/2)

123

83MHz

BF0
BF1
BF2
BF3

23

1

5.0x(5/1)

P2L-B CPU Settings

WARNING! Do not overclock your processor. Frequencies above 66MHz ex-

ceed the specifications for the onboard Intel Chipset and are not guaranteed to be
stable. Overclocking can cause undue stress on the CPU and motherboard. It
may result in a slower speed or other unpredictable outcomes. The table on the
following page shows the approved CPUs and their settings.

Set the jumpers by the Internal speed of your processor as follows:

(BUS Freq.) (Freq. Ratio)

CPU Model Speed F. Ratio BUS F. FS0 FS1 FS2 BF0 BF1 BF2 BF3

Intel Pentium II 333MHz 5.0x 66MHz [1-2] [1-2] [1-2] [2-3] [1-2] [1-2] [2-3]
Intel Pentium II 300MHz 4.5x 66MHz [1-2] [1-2] [1-2] [1-2] [2-3] [1-2] [2-3]
Intel Pentium II 266MHz 4.0x 66MHz [1-2] [1-2] [1-2] [2-3] [2-3] [1-2] [2-3]
Intel Pentium II 233MHz 3.5x 66MHz [1-2] [1-2] [1-2] [1-2] [1-2] [2-3] [2-3]

Intel Pentium II Processor in a SEC Cartridge
(233-333MHz 256/512KB L2 Cache)

NOTE: Voltage Regulator Output Selection (VID) is not needed for the Pentium II

processor because it sends a VID signal directly to the onboard power controller.

16 ASUS P2L-B User’s Manual

III. INSTALLATION

2. System Memory (DIMM)

Only Dual Inline Memory Modules (DIMM’s) can be used with this motherboard.
Three sockets are available for 3.3Volt (power level) Unbuffered Synchronous
DRAMs (SDRAM) or EDO DRAM of either 8, 16, 32, 64, or 128MB to form a
memory size between 8MB to 384MB. One side (with memory chips) of the DIMM
module takes up one Row on the motherboard.

T o utilize the chipset’s Error Checking and Correction (ECC) feature, you must use
a DIMM module with 9 chips per side (standard 8 chips/side + 1 ECC chip) which
makes 72bits (opposed to standard 64bits) and make the proper settings in the BIOS
Chipset Features Setup.

IMPORTANT: Memory speed setup is required through "Auto Configuration" in

BIOS Chipset Setup of the BIOS SOFTWARE.

WARNING: Memory modules must have 18 chips or less. Memory modules

with more that 18 chips will cause unstable operation.

Install memory in any combination as follows:

DIMM Location 168-pin DIMM Memory Modules Total Memory
Socket 1 (Rows 0&1) SDRAM/EDO 8, 16, 32, 64, 128MB x1
Socket 2 (Rows 2&3) SDRAM/EDO 8, 16, 32, 64, 128MB x1
Socket 3 (Rows 4&5) SDRAM/EDO 8, 16, 32, 64, 128MB x1

Total System Memory (Max 384MB) =

ASUS Memory Examples:

ECC EDO DIMM (9 chips)

(Jumpers)

III. INSTALLATION

Non-ECC SDRAM DIMM (8 chips)

General DIMM Notes: (not true for all memory modules)

• Four possible memory chips are supported: EDO or SDRAM with and without ECC.

• SDRAM chips are generally thinner with higher pin density than EDO chips.

• BIOS shows EDO or SDRAM memory on bootup screen.

• 8 chip/side modules do not support ECC, only 9 chip/side modules support ECC.

• Single sided modules are usually 16 or 64 MB, double sided are usually 8, 32, or 128MB.

ASUS P2L-B User’s Manual 17

DIMM Memory Installation

Insert the module(s) as shown. Because the number of pins are different on either
side of the breaks, the module will only fit in the orientation as shown. DIMM
modules are longer and have different pin contact on each side and therefore have a
higher pin density. SIMM modules have the same pin contact on both sides.

III. INSTALLATION

(System Memory)

III. INSTALLATION

20 Pins

R

60 Pins

88 Pins

Lock

P2L-B 168 Pin DIMM Memory Sockets

The Dual Inline Memory Module (DIMM) must be 3.3V Unbuffered for this moth­erboard. You can identify the type of DIMM module by the illustration below:

168-Pin DIMM Notch Key Definitions (3.3V)

DRAM Key Position

RFU

Buffered

Unbuffered

Voltage Key Position

5.0V

Reserved

3.3V

The notch on the DIMM module will shift between left, center, or right to identify the
type and also to prevent the wrong type of DIMM to be inserted into the DIMM socket
on the motherboard. Four clock signals are supported on this motherboard. You must
ask your retailer for the specifications before purchasing memory modules.

18 ASUS P2L-B User’s Manual

III. INSTALLATION

3. Central Processing Unit (CPU)

This motherboard provides a Single Edge Contact (SEC) slot for a Pentium II pro­cessor packaged in an SEC cartridge.

Pentium II Processor

WARNING! Be sure that sufficient air circulation is available across the

processor’s passive heatsink. Without sufficient circulation, the processor could
overheat and damage both the processor and the motherboard. It is recommended
that you install an auxiliary fan.

You should check to see that you have the following 9 items. (NOTE: The pictures
in the following pages will have the same item numbers next to them for your refer­ence. The design and color of your items may be slightly different.)

(1)

(2)

Attach Mount Bridges (Items 1,2)

(Factory Installed)

Top Bar (4)

(5)

Heatsink Support Base/Top Bar (Items 4-7)

Pin

Posts

(6)

Base (7)

Lock Holes

Captive Nut

(3)

Pentium II Retention Mechanism (Item 3)

(8)

Larger Fin should
be on the bottom.

Pentium II Processor Heatsink (Item 8)

Heatsink bottom Groove
for the Support Top Bar

(CPU)

III. INSTALLATION

Intel Pentium II Processor in a SEC Cartridge
(233-333MHz 256/512KB L2 Cache)

ASUS P2L-B User’s Manual 19

CPU (Item 9)

III. INSTALLATION

The Motherboard As Shipped

Four screws should be showing next to each corner of the SEC CPU Slot using two
attach mount bridges from the underside of the motherboard.

(1)

SEC CPU slot

III. INSTALLATION

(CPU)

(2)

NOTE: Encircled items are screws
from the mount bridges (1 & 2)

Installing the Pentium II Processor:

1. Mount the Pentium II Retention Mechanism: The retention mechanism is

designed to fit into the SEC slot only one way.
TIP: Orient the mechanism’ s lock holes toward the motherboard’ s chipsets (see

motherboard layout for the location of the Intel chipset).
Be sure to align the notch in the mechanism with the small rib on one side of the

slot and that the mechanism is properly seated on the board. Then, screw the
captive nuts in place.

WARNING! Do not overtighten the captive nuts. Doing so could damage your

motherboard. Tighten captive nuts to no more than 6±1 inch/pound.

Lock holes

(3)

Captive nut

20 ASUS P2L-B User’s Manual

Captive nut