...because we can't all be on the bleeding edge...





AS420/AS425/AS433/AS455

ABIT COMPUTER CORPORATION

AS420/AS425/AS433/AS455

Processor

80486SX/80486DX

Processor Speed

20/25/33/40MHz

Chip Set

SIS

Max. Onboard DRAM

32MB

Cache

32/64/128/256/512/1024KB

BIOS

AMI

Dimensions

330mm x 214mm

I/O Options

None

NPU Options

4167

CONNECTIONS

Purpose

Location

Purpose

Location

Turbo LED

D6

Reset

JP20

External battery

JP15

Speaker

JP21

Turbo switch

JP19

Power LED & keylock

JP22

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

Factory configured - do not alter

JP2

Open

Monitor type select monochrome

JP4

Open

 

Monitor type select color

JP4

Closed

CMOS memory normal operation

JP5

pins 1 & 2 closed

 

CMOS memory clear

JP5

pins 2 & 3 closed

Factory configured - do not alter

JP6

pins 1 & 2 closed

Factory configured - do not alter

JP8

pins 1 & 2 closed

Factory configured - do not alter

JP14

pins 1 & 2 closed

Factory configured - do not alter

JP17

pins 1 & 2 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 (U28 & U29)

TAG (U30)

32KB

(4) 8K x 8

NONE

(2) 16K x 4

NONE

32KB

(4) 8K x 8

NONE

NONE

(1) 8K x 8

64KB

(4) 8K x 8

(4) 8K x 8

(2) 16K x 4

NONE

64KB

(4) 8K x 8

(4) 8K x 8

NONE

(1) 8K x 8

128KB

(4) 32K x 8

NONE

(2) 64K x 4

NONE

128KB

(4) 32K x 8

NONE

NONE

(1) 32K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(2) 16K x 4

NONE

256KB

(4) 32K x 8

(4) 32K x 8

NONE

(1) 32K x 8

512KB

(4) 128K x 8

NONE

NONE

(1) 128K x 8

1024KB

(4) 128K x 8

(4) 128K x 8

(2) 64K x 4

NONE

1024KB

(4) 128K x 8

(4) 128K x 8

NONE

(1) 128K x 8

CACHE JUMPER CONFIGURATION

Size

JP28

JP30

JP31

JPX1/JPX2

JPX3

JPX4

32KB

2 & 3

Open

Closed

1 - 8

Open

1 - 16

64KB

1 & 2

Closed

Open

1 - 8

1 - 16

Open

128KB

1 & 2

Closed

Closed

3 - 10

1 - 16

Open

256KB

1 & 2

Closed

Open

5 - 12

1 - 16

Open

512KB

1 & 2

Closed

Open

7 - 14

Open

1 - 16

1024KB

1 & 2

Closed

Closed

9 - 18

1 - 16

Open

Note: Jumpers JPX1-JPX4 are closed using one or two 8-pin terminating resistors.

CPU TYPE CONFIGURATION

Type

JP25

JPX5

80486SX

Closed

Open

80486DX

Open

Closed