GIGA-BYTE TECHNOLOGY, INC.

GA-486UM

Processor

80486SX/80487SX/80486DX/ODP486SX/80486DX2

Processor Speed

16/20/25/33/50(internal)/50/66(internal)MHz

Chip Set

OPTI

Max. Onboard DRAM

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

220mm x 240mm

I/O Options

None

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J3

Turbo switch

J10

Speaker

J8

Turbo LED

J11

Power LED & keylock

J9

Reset

J12

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Monitor type select color

J6

Closed

 

Monitor type select monochrome

J6

Open

»

CMOS memory normal operation

J13

pins 1 & 2 closed

 

CMOS memory clear

J13

pins 2 & 3 closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

1MB

(4) 256K x 9

NONE

2MB

(4) 256K x 9

(4) 256K x 9

4MB

(4) 1M x 9

NONE

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

32MB

(4) 4M x 9

(4) 4M x 9

CACHE CONFIGURATION

Size

Bank 0

Bank 1

TAG

64KB

(4) 8K x 8

(4) 8K x 8

(1) 8K x 8

128KB

(4) 32K x 8

NONE

(1) 8K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

CACHE JUMPER CONFIGURATION

Size

W1

W2

W7

W9

64KB

pins 1 & 2 closed

Open

Open

Open

128KB

pins 2 & 3 closed

pins 1 & 2 closed

Open

Closed

256KB

pins 1 & 2 closed

pins 2 & 3 closed

Closed

Closed

CPU TYPE CONFIGURATION

Type

OSC Speed

W10

W11

80486SX-16

16MHz

Open

pins 2 & 3 closed

80486SX-20

20MHz

Open

pins 2 & 3 closed

80486SX-20

40MHz

Closed

pins 2 & 3 closed

80486SX-25

25MHz

Open

pins 2 & 3 closed

80487SX-25

25MHz

Open

pins 1 & 2 closed

80486DX-25

25MHz

Open

pins 1 & 2 closed

80486DX-33

33MHz

Open

pins 1 & 2 closed

80486DX-50

50MHz

Open

pins 1 & 2 closed

80486DX2-50

25MHz

Open

pins 1 & 2 closed

80486DX2-66

33MHz

Open

pins 1 & 2 closed