Gigabyte GA-486AM User Manual

GA - 486AM

USER'S MANUAL

PCI-Bus 486DX / DX2 / SX / S-Series / OverDrive / P24D / P24T / DX4 Mainboard

Rev. 1 First Edition

GA-486AM

______________________________________________________________________

The author assumes no responsibility for any errors or omissions which may appear in this document nor does it make a commitment to update the information contained herein.

IBM PC/AT, PC/XT are trademarks of International Business Machine Corporation. AWARD is a trademark of AWARD Software, Inc. Intel is a trademark of Intel Corporation, Inc. AMD is a trademark of Advanced Micro Devices, Inc. Cyrix is a trademark of Cyrix Corporation. UMC is a trademark of United Microelectronics Corporation. MS-DOS, WINDOWS NT are registered trademarks of Microsoft Corporation. UNIX is a trademark of Bell Laboratories.

Table of Contents

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Table of Contents

1.INTRODUCTION.........................................................................................................1-1

1.1.PREFACE..........................................................................................................1-1

1.2.KEY FEATURES................................................................................................1-1

1.3.PERFORMANCE LIST......................................................................................1-1

1.4.BLOCK DIAGRAM.............................................................................................1-3

1.5.INTRODUCE THE PCI-BUS ............................................................................. 1-3

2.SPECIFICATION......................................................................................................... 1-1

2.1.HARDWARE...................................................................................................... 2-1

2.2.SOFTWARE ......................................................................................................2-2

2.3.ENVIRONMENT ................................................................................................2-2

3.HARDWARE INSTALLATION .................................................................................... 3-1

3.1.UNPACKING ...................................................................................................... 3-1

3.2.MAINBOARD LAYOUT......................................................................................3-1

3.3.JUMPERS AND CONNECTORS SETTING..................................................... 3-4

3.4.SRAM INSTALLATION AND JUMPERS SETUP ............................................. 3-5

3.5.CPU INSTALLATION AND JUMPERS SETUP................................................ 3-5

3.6.DRAM INSTALLATION...................................................................................... 3-7

3.7.SPEAKER CONNECTOR INSTALLATION ...................................................... 3-7

3.8.POWER LED & KEY LOCK CONNECTOR INSTALLATION .......................... 3-7

3.9.TURBO SWITCH CONNECTOR INSTALLATION........................................... 3-7

3.10.TURBO LED FLASH GREEN LED CONNECTOR INSTALLATION..............3-7

3.11.HARDWARE RESET SWITCH CONNECTOR INSTALLATION................... 3-8

3.12.GREEN FUNCTION INSTALLATION.............................................................. 3-8

3.13.PERIPHERAL DEVICE INSTALLATION.........................................................3-8

3.14.SOME IMPORTANT APPLICATION NOTES ................................................. 3-8

4.BIOS CONFIGURATION.............................................................................................4-1

4.1.ENTERING SETUP ........................................................................................... 4-1

4.2.CONTROL KEYS............................................................................................... 4-1

4.3.GETTING HELP ................................................................................................ 4-2

4.3.1.Main Menu................................................................................................. 4-2

4.3.2.Status Page Setup Menu / Option Page Setup Menu................................4-2

4.4.THE MAIN MENU .............................................................................................. 4-2

4.5.STANDARD CMOS SETUP MENU .................................................................. 4-4

4.6.BIOS FEATURES SETUP................................................................................. 4-7

4.7.CHIPSET FEATURES SETUP.......................................................................... 4-9

4.8.POWER MANAGEMENT SETUP.....................................................................4-13

4.9.PCI /GREEN FUNCTION SETUP..................................................................... 4-15

4.10.LOAD BIOS DEFAULTS.................................................................................. 4-17

4.11.LOAD SETUP DEFAULTS...............................................................................4-18

4.12.PASSWORD SETTING...................................................................................4-19

4.13.IDE HDD AUTO DETECTION.........................................................................4-20

4.14.SAVE & EXIT SETUP ...................................................................................... 4-21

4.15.EXIT WITHOUT SAVING ................................................................................ 4-22

4.16.KEYBOARD SETTING FUNCTION.................................................................4-22

5.AT TECHNICAL INFORMATION................................................................................5-1

5.1.BUS CONNECTOR PIN OUT ........................................................................... 5-1

5.1.1.ISA BUS SLOT PIN OUT ......................................................................... 5-1

5.1.2.PCI BUS SLOT PIN OUT.........................................................................5-2

GA-486AM

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5.2.I/O & MEMORY MAP.........................................................................................5-3

5.3.TIMER & DMA CHANNELS MAP......................................................................5-3

5.4.INTERRUPT MAP ............................................................................................. 5-4

5.5.RTC & CMOS RAM MAP .................................................................................. 5-4

APPENDIX A: POST MESSAGE....................................................................................A-1

APPENDIX B: POST CODES.........................................................................................B-1

APPENDIX C: BIOS DEFAULT DRIVE TABLE............................................................. C-1

APPENDIX D: PROBLEM SHEET ................................................................................. D-1

Introduction

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1-1

1INTRODUCTION

1.1 PREFACE

Welcome to use the GA-486AM motherboard. The motherboard is a 128 KB - 1 MB CACHE 486DX series PC/AT compatible system with ISA bus, PCI (Peripheral Component Interconnect) bus and has been designed to be the fastest 486 PC/AT system and the GREEN FUNCTION (Power-Down Mode) had been added. There are some new features allowing you to operate the system with just the performance you want.

This manual also explains how to install the motherboard for operation, and how to set up your CMOS CONFIGURATION with BIOS SETUP program.

1.2 KEY FEATURES

• 80486 based PC/AT compatible mainboard with ISA and PCI Bus.

• Supports 3 Master PCI bus slots .

• Supports 486DX / DX2 / SX / S-Series / OverDrive / P24D / P24T / DX4 running at 25 -

100 MHz.

• Supports True Green Function.

• Supports Intel, AMD, Cyrix and UMC CPU.

• Supports 237 pin (Socket 3) ZIF White socket / LIF socket on board.

• Supports 128 / 256 / 512 KB / 1 MB 2nd cache memory operated in BURST mode.

• Write-Back cache operation.

• Supports 2 - 128 MB DRAM memory on board.

• Supports 2 channels Enhance PCI IDE ports for 4 IDE Devices.

• Supports 2xCOM (16550) ports, 1xLPT (EEP / ECP) port, 1 Floppy port.

• Supports shadow RAM for BIOS & VIDEO BIOS.

• Supports shadow RAM cacheable function to improve performance.

• Supports Hardware & Software speed change function.

• Licensed AWARD BIOS.

• 2/3 Baby AT size (22 cm x 25 cm) with 4 AT slots and 3 PCI slots .

1.3 PERFORMANCE LIST

The following performance data list is the testing results with some popular benchmark testing programs. These datas are just reference for users and there is no responsibility for different testing data values gotten by users.( The different H/W & S/W configuration will result in different benchmark testing results.)

GA-486AM

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1-2

System Benchmarks At DOS Environment with IDE Controller

• CPU : 486DX4-100/75,DX2-80/66/50,DX-40/33/P24T 63 • Config.sys: • Autoexec.bat:

• DRAM : 32 MB / 70ns DEVICE = C:\DOS\SETVER.EXE C:\DOS\SMARTDRV.EXE /X

•

CACHE : 256KB DEVICE = Using Default Setting @ECHO OFF

• VGA : Genoa S3/864 2MB DRAM DEVICE = C:\DOS\HIMEM.SYS PROMPT $p$g

• H.D. : Seagate ST31220A ( 1GB ) DOS = HIGH PATH C:\;C:\DOS

• O.S. : MS DOS V6.22 FILES = 30 SET TEMP = C:\DOS

¡° Using Intel DX4-100 / 75

Software Item Unit P24T 63WBDX4-100x3 DX4-75x3 DX2-80

LandMark Speed CPU MHz 360.77 363.39 272.57 267.74 V2.0 FPU MHz 1038.62 883.65 662.79 704.77

Video chr/ms 12288 16384 12288 12603 Norton SI CPU index 198.1 198.1 148.6 158.5 V8.0 DISK index 19.3 19.3 19.3 17.0

Overall index 137.3 138.4 105.4 111.2 Power Meter MIPS Mips 28.7 29.6 22.2 23.5 V1.81 CPU/MEM Agg. PMUs 44895.7 39237.0 29466.0 31067.3

Data-Xfer KB/sec 8058.5 8058.5 8058.5 8058.5

DISK Agg. PMUs 1183.6 1281.4 1284.5 1284.5 PC Bench mark DOS Mark index 593.41 605.45 494.76 485.98 V9.0 CPU mark 16 index 116.02 113.52 86.91 86.21

Video Score index 3350.31 4334.13 3482.11 3469.10

DISK Score index 391.29 393.86 345.22 334.53

Software Item Unit DX2-66 DX2-50 DX-40 DX-33 LandMark Speed CPU MHz 223.08 167.43 133.87 111.53 V2.0 FPU MHz 589.08 441.38 353.49 294.52

Video chr/ms 16384 1228 12603 16384 Norton SI CPU index 144.1 108.1 86.4 72.0 V8.0 DISK index 19.4 19.3 16.8 19.3

Overall index 102.4 78.4 63.2 54.4 Power Meter MIPS Mips 21.2 15.9 13.0 10.9 V1.81 CPU/MEM Agg. PMUs 25764.7 19428.7 15604.0 13009.0

Data-Xfer KB/sec 8058.5 8058.5 8058.5 8058.5

DISK Agg. PMUs 1284.5 1284.7 1286.2 1288.5 PC Bench mark DOS Mark index 478.69 384.52 336.45 304.09 V9.0 CPU mark 16 index 84.07 63.85 53.91 47.17

Video Score index 4309.58 3462.69 3439.79 4251.11

DISK Score index 319.19 272.82 244.17 220.67

Introduction

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1-3

1.4 BLOCK DIAGRAM

80486

Cache SRAM

UM8881F

OSC

Clock Buffer

BIOS ROM

AT Bus

Memory DRAM

MA,RAS,CAS

SD<0..15> SA<0..15>

8 MHz

UM8886AF

PCI Bus

Clock Buffer

1 2

IDE

CTRL Buffer

DATA Buffer

1.5 INTRODUCE THE PCI-BUS

Connecting devices to a local bus of CPU can dramatically increase the speed of I/O-bound peripherals with only a slight increase in cost over traditional systems. This price/performance point has created a vast market potential for local bus products. The main barrier to this market has been the lack of an accepted standard for local bus peripherals.

The PCI-bus standard, under development since Jun. 1992, which is designed to bring workstation-level performance to standard PC platform. The PCI-bus removes many of the bottlenecks that have hampered PC for several years. On the PCI-bus, peripherals operate at the native speed of the computer system, thus enabling data transfer between peripherals and the system at maximum speed. This performance is critical for bandwidthconstrained devices such as video, multimedia, mass storage and networking adapters.

PCI-bus standard provide end-users with a low-cost, extendible and portable local bus design, which will allow systems and peripherals from different manufacturers to work together.

GA-486AM ______________________________________________________________________

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2-1

2 SPECIFICATION

2.1 HARDWARE

• CPU − 80486SX/DX/DX2/S-Series, 80487SX, OverDrive, P24D,

P24T, DX4.

− 237 pins (Socket 3) ZIF white socket / LIF socket on

board.

• COPROCESSOR − Coprocessor included in 80486DX.

• SPEED − 25 / 33 / 40 / 50 MHz system

− 20-33 MHz PCI- bus speed.

− 8 MHz (programmable) AT Bus speed.

− Hardware and Software speed switchable function.

• GREEN FUNCTION − Power Down Timer from 0.25 min to 512 min.

− When enter Power Down Mode, 8 MHz system speed for

non S-Series and 0 MHz system speed for Intel & Cyrix SSeries.

− Ext. Power Control Port for Monitor Power ON / OFF

− Support IDE Hard Disk Standby Mode control.

− Wake Up by all IRQ, DMA, and PCI Master Devices.

− Support Green LED Indicator and Green Switch.

• DRAM MEMORY − 2 banks 72 pins SIMM module sockets on board.

− Use 1 / 2 / 4 / 8 / 16 / 32 MB 70 ns SIMM module DRAM.

− Support Fast Page DRAM access mode.

• CACHE MEMORY − 8 KB cache memory included in 80486 DX / SX / DX2 /

SX2 and AMD DX4.

− 16 KB cache memory included in INTEL DX4.

− 128 / 256 / 512 KB / 1 MB 2nd cache memory on board.

− Support 486 Burst mode on 2nd cache memory access.

• SHADOW RAM − Main BIOS shadow function programmable.

− Video BIOS shadow function programmable.

− Shadow RAM cacheable function programmable.

• IDE PORTS − 2 Enhanced IDE channels on board.(Using IRQ14,15)

− Support Mode 3 IDE & ATAPI CD-ROM.

− Driver Support DOS, WINDOWS, OS/2, NT, Novell.

• I/O PORTS − Supports 2 16550 COM ports. (Using IRQ4,3)

− Supports 1 EPP/ECP LPT port. (Using DMA3 & IRQ7)

− Supports Floppy port. (Using DMA2 & IRQ6)

• I/O BUS SLOTS − 4 AT-bus.

− 3 PCI-bus.

• DIMENSION − 2/3 Baby AT size (22 cm x 25 cm).

Specification

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2-2

2.2 SOFTWARE

• BIOS − Licensed AWARD BIOS.

− AT CMOS Setup, Advanced / Chipset Setup and Power

Management included.

• O. S. − Operation with MS-DOS, WINDOWS NT,OS/2,

NOVELL, SCO UNIX.

2.3 ENVIRONMENT

• AMBIENT TEMP.

− 0°C to +50°C (operating).

• RELATIVE HUM. − 0 to +85% (operating).

• ALTITUDE − 0 to 10,000 feet (operating).

• VIBRATION − 0 to 1,000 Hz.

• ELECTRICITY − 4.9 V to 5.2 V.

− 3 A to 5 A current.

GA-486AM ______________________________________________________________________

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3-1

3 HARDWARE INSTALLATION

3.1 UNPACKING

The ainboard ackage hould ontain he ollowing:

• The A-486AM ainboard

• User's manual

• A Driver Diskette

The mainboard contains sensitive electric components which can be easily damaged by static electricity, so the mainboard should be left in its original packing until it is installed.

Unpacking and installation should be done on a grounded anti-static mat. The operator should be wearing an anti static wristband, grounded at the same point as the anti-static mat.

Inspect the mainboard carton for obvious damage. Shipping and handling may cause damage to your board. Be sure there are no shipping and handling damages on the board before proceeding.

After opening the mainboard carton, extract the system board and place it only on a grounded anti-static surface component side up. Again inspect the board for damage. Press down on all of the socket IC's to make sure that they are properly seated. Do this only on with the board placed on a firm flat surface.

Do not apply power to the board if it has been damaged..

You are now ready to install your mainboard. The mounting hole pattern on the mainboard matches the IBM-XT system board. It is assumed that the chassis is designed for a standard IBM XT/AT mainboard mounting.

Place the chassis on the anti-static mat and remove the cover. Take the plastic clips, Nylon stand-off and screws for mounting the system board, and keep them separate.

3.2 MAINBOARD LAYOUT

×GA-486AMØ

JP12

JP9

JP8

JP10

JP5

BIOS

271024

DS12887

CPU

JP23

JP15

82C8881

82C8886AF

SIMM 1

SIMM 3

SIMM 2

PCI 3 SUGGEST DISPLAY

PCI 1

PCI 2

SIMM 4

PS1

KB1

UM8663

FLOPPY CN3

PRINT PORT CN4

129

COM1/3 COM2/4

CN6

CN5

GA-486AM

JP25

GN PW

TAG RAM

D A T A

C A C H E

JP14

JP13

SLOT 2

SLOT 4

SLOT 6

SLOT 8 SLOT 7

SLOT 5

SLOT 3

SLOT 1

JP22

1 1 1 1

+++

JP18JP19

314

JP11

111111111

R N 1

R N 2

R N 3

R N 4

R N 5

JP24

JP26

U28 U27

U30

U32

U34

U29

U31

U33

612

CN1 IDE1 CN2 IDE2

JP20

Hardware Installation

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3-2

JP15

1-2

JP15

3-4

JP15

5-6

RN1 RN2 RN3 RN4 RN5 JP5

1-2

JP5 3-4

JP5

5-6

JP5 7-8

INTEL SX-25/SX2-50 O X X X O X X O X O O X INTEL SX-25/SX2-50 S-CPU O X X X O X X O X O O X INTEL DX-25/DX2-50 O X X X O X X O X O O X INTEL DX-25/DX2-50 S-CPU O X X X O X X O X O O X INTEL P24T 63 WT O X X X O X X O X O O X INTEL P24T 63 WB O X X X O X X O X O O X INTEL DX4-75(25x3) S-CPU O X X X O X X O X O O X INTEL SX-33/SX2-66 O O O X O X X O X O O X INTEL SX-33/SX2-66 S-CPU O O O X O X X O X O O X INTEL DX-33/DX2-66 O O O X O X X O X O O X INTEL DX-33/DX2-66 S-CPU O O O X O X X O X O O X INTEL P24T 83 WT O O O X O X X O X O O X INTEL P24T 83 WB O O O X O X X O X O O X INTEL DX-33 OVERDRIVE O O O X O X X O X O O X INTEL DX-33 OVERDRIVE S-CPU O O O X O X X O X O O X INTEL P24D WT S-CPU O O O X O X X O X O O X INTEL P24D WB S-CPU O O O X O X X O X O O X AMD Enhance DX2-66 WT O O O X O X X O X O O X AMD Enhance DX2-66 WB O O O X O X X O X O O X INTEL DX4-100(33X3) S-CPU O O O X O X X O X O O X AMD Enhance DX4-100 WT O O O X O X X O X O O X AMD Enhance DX4-100 WB O O O X O X X O X O O X INTEL DX4-OVERDRIVE(33X3) S-CPU O O O X O X X O X O O X INTEL DX4-100(50X2) S-CPU NOT-RECOMMEND X X O X O X X O X O O X AMD SX-25/SX2-50 O X X X O X X O X O O X AMD DX-25/DX2-50 O X X X O X X O X O O X AMD SX-33/SX2-66 O O O X O X X O X O O X AMD DX-33/DX2-66 O O O X O X X O X O O X AMD SX-40/SX2-80 O O X X O X X O X O O X AMD DX-40/DX2-80 O O X X O X X O X O O X AMD Enhance DX2-80 WT O O X X O X X O X O O X AMD Enhance DX2-80 WB O O X X O X X O X O O X AMD DX4-100 (Not Enhance) O O O X O X X O X O O X 5V Cyrix SX-25/SX2-50 S-CPU O X X O X X O X O O X X 5V Cyrix DX-25/DX2-50 S-CPU O X X O X X O X O O X X 5V Cyrix SX-33/SX2-66 S-CPU O O O O X X O X O O X X 5V Cyrix DX-33/DX2-66 S-CPU O O O O X X O X O O X X

3.3 Cyrix DX2-66 S-CPU O O O O X X O X O O X X 4V Cyrix DX2-80 S-CPU O O X O X X O X O O X X UMC SX-33 S-CPU O O O X X O X X X X O O UMC SX-40 S-CPU O O X X X O X X X X O O

O : Jumper or Resistor installed. X : Jumper or Resistor not installed.

GA-486AM ______________________________________________________________________

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3-3

JP8

1-2

JP8 3-4

JP9 JP11

1-2

JP11

2-3

JP12

1-2

JP12

2-3

JP10 JP23

1-2

JP23

2-3

JP22 JP13 JP20

INTEL SX-25/SX2-50 O X O X O X O X O X X O O INTEL SX-25/SX2-50 S-CPU X O O X O X O X O X X O O INTEL DX-25/DX2-50 O X O O X X O X O X X O O INTEL DX-25/DX2-50 S-CPU X O O O X X O X O X X O O INTEL P24T 63 WT X O O O X X O X O X X O O INTEL P24T 63 WB X O O O X X O X O X X O X INTEL DX4-75(25x3) S-CPU X O O O X X O X O X X X O INTEL SX-33/SX2-66 O X O X O X O X O X X O O INTEL SX-33/SX2-66 S-CPU X O O X O X O X O X X O O INTEL DX-33/DX2-66 O X O O X X O X O X X O O INTEL DX-33/DX2-66 S-CPU X O O O X X O X O X X O O INTEL P24T 83 WT X O O O X X O X O X X O O INTEL P24T 83 WB X O O O X X O X O X X O X INTEL DX-33 OVERDRIVE O X O O X X O X O X X O O INTEL DX-33 OVERDRIVE S-CPU X O O O X X O X O X X O O INTEL P24D WT S-CPU X O O O X X O X O X X O O INTEL P24D WB S-CPU X O O O X O X X O X X O O AMD Enhance DX2-66 WT X O X O X X O X O X X O O AMD Enhance DX2-66 WB X O X O X O X X O X X O O INTEL DX4-100(33X3) S-CPU X O O O X X O X O X X X O AMD Enhance DX4-100 WT X O X O X X O X O X X O O AMD Enhance DX4-100 WB X O X O X O X X O X X O O INTEL DX4-OVERDRIVE(33X3) S-CPU X O O O X X O X O X X X O INTEL DX4-100(50X2) S-CPU NOT-RECOMMEND X O O O X X O O O X X X O AMD SX-25/SX2-50 O X X X O X O X O X X O O AMD DX-25/DX2-50 O X X O X X O X O X X O O AMD SX-33/SX2-66 O X X X O X O X O X X O O AMD DX-33/DX2-66 O X X O X X O X O X X O O AMD SX-40/SX2-80 O X X X O X O X O X X O O AMD DX-40/DX2-80 O X X O X X O X O X X O O AMD Enhance DX2-80 WT X O X O X X O X O X X O O AMD Enhance DX2-80 WB X O X O X O X X O X X O O AMD DX4-100 (Not Enhance) O X X O X O X X O X X O O 5V Cyrix SX-25/SX2-50 S-CPU O X O X O X O X O X X O O 5V Cyrix DX-25/DX2-50 S-CPU O X O O X X O X O X X O O 5V Cyrix SX-33/SX2-66 S-CPU O X O X O X O X O X X O O 5V Cyrix DX-33/DX2-66 S-CPU O X O O X X O X O X X O O

3.3 Cyrix DX2-66 S-CPU O X O O X X O X X O X O O 4V Cyrix DX2-80 S-CPU O X O O X X O X X O O O O UMC SX-33 S-CPU O X X X O X O X O X X O O UMC SX-40 S-CPU O X X X O X O X O X X O O

O : Jumper or Resistor installed. X : Jumper or Resistor not installed.

Hardware Installation

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3-4

3.3 JUMPERS AND CONNECTORS SETTING

• CONNECTOR SETTING

J1: Reset Connector Open Normal operation. Close Hardware reset system.

J2: Turbo Switch Connector Close Low speed. Open High speed. (Default)

J3: Speaker Connector 1 Data. 2 GND. 3 GND. 4 VCC (+5V).

J4: Power LED & Key-Lock Connector 1 LED anode (+). 2 NC. 3 LED cathode (-). 4 Key-lock. 5 GND.

JP1: HDD LED (On board layout, "+" is LED anode)

Hard disk Read/Write indicator.

KB1: Keyboard Connector 1 Keyboard clock. 2 Keyboard data. 3 NC. 4 VCC (+5V). 5 GND.

PS1: Power Supply Connector 1 Power good signal. 2,10,11,12 VCC (+5V). 3 +12V. 4 -12V. 5,6,7,8 GND. 9 -5V.

• GREEN FUNCTION JUMPER SETTING

JP2: Turbo LED and Flash Green LED (On board layout, "+" is LED anode)

Normally, this jumper is for Turbo LED. But when system gets into Green mode, the LED on this jumper will light on once per second.

JP3: Brake Switch

Shorting this jumper and then releasing it immediately will force system

GA-486AM ______________________________________________________________________

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3-5

into Green mode right away.

JP4: Green LED (On board layout, "+" is LED anode)

When system gets into Green, the LED on this jumper will be light.

JP25: Green Power Connector (On board layout, "+" is positive voltage)

If your power supply has signal to control the A.C. output, and then the signal can be connected to this connector; when system gets into Green mode, your power supply A.C. output will be turned OFF. By this way, you can control your monitor ON/OFF or other devices.

3.4 SRAM INSTALLATION AND JUMPERS SETUP

The cache memory system consists of two parts, one is TAG SRAM, the other is DATA SRAM. The TAG SRAM type used in this mainboard is 8Kx8, 16Kx8, 32Kx8 or 64Kx8 15ns, and the DATA SRAM type is 8Kx8-15ns, 32Kx8-15ns 64Kx8-20ns or 128Kx8-20ns.

The mainboard can be installed with 128, 256, 512 KB or 1MB cache memory when using 8Kx8 or 32Kx8 or 64Kx8 or 128Kx8 type DATA SRAM respectively.

• CACHE MEMORY SIZE SETTING

Size 128K* 256K 256K* 512K 512K* 1M JP24 1-2 OPN SHT SHT SHT SHT SHT JP24 3-4 OPN OPN OPN SHT SHT SHT JP24 5-6 OPN OPN OPN OPN OPN SHT JP26 3-5 1-3 3-5 2-4 3-5 4-6

DATA SRAM

32K8 4 pcs 32K8 8 pcs 64K8 4 pcs 64K8 8 pcs 128K8 4 pcs 128K8 8 pcs

TAG SRAM

8K8 16K8 16K8 32K8 32K8 64K8

¡¯ U28, U30, U32, U34 Installed only.

3.5 CPU INSTALLATION AND JUMPERS SETUP

The CPU is a sensitive electric component and it can be easily damaged by static electricity, so users must keep it away from metal surface when the CPU is installed onto mainboard.

When the user installs the CPU on socket, please notice the PIN 1 of CPU is in the same corner as the PIN 1 of socket!

Before the CPU is installed, the mainboard must be placed on a flat plane in order to avoid being broken by the pressure of CPU installation.

• CPU CLOCK SETTING

The system speed depends on the frequency of CLOCK GENERATOR. The user can change the clock selection jumper to set up the system speed at 25, 33 ,40 or 50 MHz for different CPU speeds.

The mainboard can use 80486DX, DX2, SX, SX2 OverDrive, P24T, P24D and DX4 CPU, and the CPU speed must match with the frequency of CLOCK GEN. It will cause system hanging up if the CLOCK GEN.'S frequency is higher than CPU's.

Refer to the following table to set up the CPU clock:

Hardware Installation

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3-6

Clock JP15

1-2 3-4 5-6 25 MHz Short Open Open 33 MHz Short Short Short 40 MHz Short Short Open 50 MHz Open Open Short

• CPU BRAND SELECTION

BRAND JP5 RN1 RN2 RN3 RN4 RN5 Intel, AMD 3-4, 5-6 Installed Installed Cyrix 1-2, 3-4 Installed Installed UMC 5-6, 7-8 Installed

• CPU TYPE SELECTION

JP8:

1-2 Others. 2-3 Intel S series, AMD Enhance series.

JP9:

Close Others. Open AMD, UMC.

JP10:

Close Intel DX4 & AMD Enhance x 2. Open Intel DX4 & AMD Enhance x 3.

JP11:

1-2 For DX CPU. 2-3 For SX CPU.

JP12:

1-2 P24D & AMD Enhance WB, AMD DX4 x 3 (Not Enhance Type). 2-3 P24D & AMD Enhance WT, AMD DX4 x 2 (Not Enhance Type).

JP13:

Close Others. Open Intel DX4 & Intel DX4 OverDrive.

• CPU VOLTAGE SELECTION

JP22 JP23 INTEL AMD Cyrix UMC Open 1-2 3.3V, 5V 3.3V, 5V 5V 5V Open 2-3 3.3V Close 2-3 4V

JP20:

Close P24T WT. Open P24T WB.

Note: Please remember set CPU internal cache to WB in BIOS CHIPSET FEATURES

SETUP, if you already set JP12 or JP20 to support WB CPU.

GA-486AM ______________________________________________________________________

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3.6 DRAM INSTALLATION

This mainboard can be installed with 1, 2, 4, 8, 16 or 32 MB 72 pins SIMM module DRAM. The DRAM speed of both mainboard is using 60/70 ns. The banks of memory system on the mianboard includes from SIMM 1 to SIMM 4.

SIMM 1 and SIMM 2 is a group; SIMM 3 and SIMM 4 is the other group. One group DRAM size can be 2, 4, 8, 16, 32, 64 MB, please install the same DRAM size in one group. Total DRAM size is 2 MB ~ 128 MB.

The DRAM installation position refer to MAINBOARD LAYOUT, and notice the PIN -1 of SIMM module must match with the PIN -1 of SIMM socket when the DRAM SIMM module is installed.

Insert the DRAM SIMM module into the SIMM socket at 45 degree angle. If there is a wrong direction of PIN -1, the DRAM SIMM module couldn't be inserted into socket completely. After completely insert SIMM module into socket, then press the SIMM module in vertical direction until the left and right metal holders can keep the SIMM module standing up con-firmly.

3.7 SPEAKER CONNECTOR INSTALLATION

There is always a speaker in AT system for sound purpose. The 4-Pins connector (J3) is used to connect speaker. The speaker can work well in both direction of connector when it is installed to the connector (J3) on mainboard.

3.8 POWER LED & KEY LOCK CONNECTOR INSTALLATION

There are a system power LED lamp and a key on the panel of case. The power LED will light on when system is powered-on, and the key can lock the keyboard input or unlock it, both of them are connected to a 5 PIN connector. The connector should be installed to J4 of mainboard in correct direction.

3.9 TURBO SWITCH CONNECTOR INSTALLATION

The TURBO switch on the panel is used for controlling the system speed. Some program developed on XT should be executed with a low speed system, so a high speed system needs the speed switching function to change its running speed.

Because a 80486 CPU cannot accept the real clock speed change when program is executed, so the mainboard uses cache-enable or disable function to simulate TURBO switching function. The J2 on mainboard should be connected to the TURBO switch on panel, and user can push in or pop out the TURBO switch to enable or disable the cache function of system.

3.10TURBO LED FLASH GREEN LED CONNECTOR INSTALLATION

The TURBO LED on panel can indicate the current speed status of system. The TURBO LED connector should be installed to JP2 in correct direction. Normally, the JP2 is a TURBO LED connector. But when system gets into Green mode, the LED on JP2 will light on once per second.

Hardware Installation

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3.11HARDWARE RESET SWITCH CONNECTOR INSTALLATION

The Reset switch on panel provides users with Hardware Reset function which is almost the same as power on / off. The system will do a cold start after the Reset switch is pushed and released at once. The Reset switch is a 2 PIN connector and should be installed to J1 on mainboard.

3.12GREEN FUNCTION INSTALLATION

For the purpose of power saving, there are two jumpers, JP4 and JP3, to make sure the power saving function doing well. The JP4 is a indicator (Green LED) for Green function. If the green LED is ON, the system is operating in green mode. The JP3 is a switch to force the system into Green mode immediately.

3.13PERIPHERAL DEVICE INSTALLATION

If a PCI-bus device is to be installed in the system, any one of three PCI-bus slots can be used no matter what Slave or Master PCI-bus device being installed.

After the peripheral device installed, the user should check everything again, and prepare to power-on the system. Now, the mainboard can be mounted into the case and fixed with screws.

3.14SOME IMPORTANT APPLICATION NOTES

For compatibility, there are some special application notes the users should know. Note 1: (AHA 2940 or AHA 3940 or BT 946C PCI SCSI) AND (S3 928 or WD 90C33 PCI

Display) Please put PCI SCSI CARD in PCI slot1 & PCI Display CARD in PCI slot3 & set Jumper JP14 2-3 short Jumper JP19 open.

Note 2: (Future Domain or NCR 810 or AHA 3940 PCI SCSI) AND (ET 4000/W32P or S3

864 or S3 964 PCI Display) Please put PCI SCSI Display CARD in PCI slot1 or slot2 & PCI Display CARD in PCI slot3 & set Jumper JP18 1-2 short.

Note 3: In order to configure BT 946C PCI SCSI, Please put BT 946C in PCI slot3 & set

Jumper JP18 1-2 short. After configuration, you may put BT 946C in any one of the PCI slots.

Otherwise, Please keep JP14 pin 1-2 short, JP19 close, JP18 pin 2-3 short.

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Gigabyte GA-486AM User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual