GIGA-BYTE TECHNOLOGY CO., LTD.

GA-486AM/AMS (REV. 2),

GA-486AM/AMS (REV. 2.1)

Processor

CX486/AM486/UMC/SL80486SX/80486SX/SL80486DX/80486DX/ SL80486DX2/80486DX2/P24D/AM486DX4/80486DX4/Pentium Overdrive

Processor Speed

25/33/40/50(internal)/50/66(internal)/75(internal)/100(internal)MHz

Chip Set

UMC

Max. Onboard DRAM

128MB

Cache

128/256/512/1024KB

BIOS

Award

Dimensions

250mm x 220mm

I/O Options

32-bit PCI slots (3), floppy drive interface, green PC connector, IDE interfaces (2), parallel port, serial ports (2)

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

IDE interface 1

CN1

Speaker

J3

IDE interface 2

CN2

Power LED & keylock

J4

Floppy drive interface

CN3

IDE interface LED

JP1

Parallel port

CN4

Turbo LED

JP2

Serial port 2

CN5

Green PC connector

JP3

Serial port 1

CN6

Green PC LED

JP4

Reset switch

J1

Green PC connector

JP25

Turbo switch

J2

32-bit PCI slots

PC1 - PC3

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Factory configured - do not alter

JP14

Pins 1 & 2 closed

»

Factory configured - do not alter

JP18

Pins 2 & 3 closed

»

Factory configured - do not alter

JP19

Closed

»

Cache type select write through

JP20

Closed

 

Cache type select write back

JP20

Open

DRAM CONFIGURATION

Size

Bank 0

Bank 1

2MB

(2) 256K x 36

NONE

4MB

(2) 256K x 36

(2) 256K x 36

6MB

(2) 512K x 36

(2) 256K x 36

8MB

(2) 1M x 36

NONE

10MB

(2) 1M x 36

(2) 256K x 36

12MB

(2) 1M x 36

(2) 512K x 36

16MB

(2) 2M x 36

NONE

18MB

(2) 2M x 36

(2) 256K x 36

20MB

(2) 2M x 36

(2) 512K x 36

24MB

(2) 2M x 36

(2) 1M x 36

32MB

(2) 4M x 36

NONE

34MB

(2) 4M x 36

(2) 256K x 36

36MB

(2) 4M x 36

(2) 512K x 36

40MB

(2) 4M x 36

(2) 1M x 36

48MB

(2) 4M x 36

(2) 2M x 36

64MB

(2) 8M x 36

NONE

66MB

(2) 8M x 36

(2) 256K x 36

68MB

(2) 512K x 36

(2) 8M x 36

72MB

(2) 8M x 36

(2) 1M x 36

80MB

(2) 8M x 36

(2) 2M x 36

96MB

(2) 8M x 36

(2) 4M x 36

128MB

(2) 8M x 36

(2) 8M x 36

CACHE CONFIGURATION

Size

Bank 0

Bank 1

TAG

128KB

(4) 32K x 8

NONE

(1) 8K x 8

256KB (A)

(4) 32K x 8

(4) 32K x 8

(1) 16K x 8

256KB (B)

(4) 64K x 8

NONE

(1) 16K x 8

512KB (A)

(4) 64K x 8

(4) 64K x 8

(1) 32K x 8

512KB (B)

(4) 128K x 8

NONE

(1) 32K x 8

1MB

(4) 128K x 8

(4) 128K x 8

(1) 64K x 8

CACHE JUMPER CONFIGURATION

Size

JP24

JP26

128KB

Open

Pins 3 & 5 closed

256KB (A)

Pins 1 & 2 closed

Pins 1 & 3 closed

256KB (B)

Pins 1 & 2 closed

Pins 3 & 5 closed

512KB (A)

Pins 1 & 2, 3 & 4 closed

Pins 2 & 4 closed

512KB (B)

Pins 1 & 2, 3 & 4 closed

Pins 3 & 5 closed

1MB

Pins 1 & 2, 3 & 4, 5 & 6 closed

Pins 4 & 6 closed

CPU TYPE CONFIGURATION

Type

RN1

RN2

RN3

RN4

RN5

Cyrix

Installed

Not installed

Not installed

Installed

Not installed

AMD

Not installed

Installed

Not installed

Not installed

Installed

UMC

Not installed

Not installed

Installed

Not installed

Not installed

Intel

Not installed

Installed

Not installed

Not installed

Installed

CPU TYPE CONFIGURATION

Type

JP8

All CPU types

Pins 1 & 2 closed

Intel S-series

Pins 3 & 4 closed

AMD S-series

Pins 3 & 4 closed

CPU TYPE CONFIGURATION

Type

JP9

All CPU types

Closed

AMD

Open

UMC

Open

CPU TYPE CONFIGURATION

Type

JP11

80486SX

Pins 2 & 3 closed

80486DX

Pins 1 & 2 closed

CPU TYPE CONFIGURATION

Type

JP13

All CPU types

Closed

80486DX4

Open

CPU TYPE CONFIGURATION

Type

JP5

Cyrix

Pins 1 & 2, 3 & 4 closed

AMD

Pins 3 & 4, 5 & 6 closed

UMC

Pins 5 & 6, 7 & 8 closed

Intel

Pins 3 & 4, 5 & 6 closed

CPU SPEED CONFIGURATION

Speed

JP15

25MHz

Pins 1 & 2 closed

33MHz

Pins 1 & 2, 3 & 4, 5 & 6 closed

40MHz

Pins 1 & 2, 3 & 4 closed

50iMHz

Pins 1 & 2 closed

50MHz

Pins 5 & 6 closed

66iMHz

Pins 1 & 2, 3 & 4, 5 & 6 closed

75iMHz

Pins 1 & 2 closed

100iMHz

Pins 1 & 2, 3 & 4, 5 & 6 closed

CPU SPEED CONFIGURATION (P24D & AM486DX4 ONLY)

Speed

JP12

2x

Pins 2 & 3 closed

3x

Pins 1 & 2 closed

CPU SPEED CONFIGURATION (80486DX4 ONLY)

Speed

JP10

2x

Closed

3x

Open

CPU VOLTAGE CONFIGURATION

Processor Type

Voltage

JP22

JP23

Intel/AMD

3.3v

Open

Pins 1 & 2 closed

Cyrix

3.3v

Open

Pins 2 & 3 closed

Cyrix

4v

Closed

Pins 2 & 3 closed

Intel/AMC/Cyrix/UMC

5v

Open

Pins 1 & 2 closed