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





AT4

ABIT COMPUTER CORPORATION

AT4

Processor

80486SX/80486DX/P23T

Processor Speed

16/25/33/50MHz

Chip Set

Unidentified

Video Chip Set

None

Maximum Onboard Memory

32MB

Maximum Video Memory

None

Cache

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

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

None

NPU Options

4167

CONNECTIONS

Purpose

Location

Purpose

Location

Speaker

CN1

Turbo switch

JP1

Power LED & keylock

CN2

Turbo LED

JP2

External battery

CN3

Reset switch

SW1

USER CONFIGURABLE SETTINGS

Function

Label

Position

»

CMOS memory normal operation

JP5

Pins 1 & 2 closed

 

CMOS memory clear

JP5

Pins 2 & 3 closed

 

Monitor type select CGA/EGA/VGA

JP7

Closed

 

Monitor type select monochrome

JP7

Open

»

Factory configured - do not alter

JP8

Open

»

Factory configured - do not alter

JP9

Open

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

TAG0

32KB

(4) 8K x 8

None

(1) 8K x 8

(2) 16K x 4

64KB

(4) 8K x 8

(4) 8K x 8

(1) 8K x 8

(2) 16K x 4

128KB

(4) 32K x 8

None

(1) 8K x 8

(2) 16K x 4

256KB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

(2) 16K x 4

512KB

(4) 128K x 8

None

(1) 32K x 8

(2) 64K x 4

1MB

(4) 128K x 8

(4) 128K x 8

(1) 128K x 8

(2) 64K x 4

Note: Use either TAG chip or TAG0 chips. All three sockets can’t be installed at the same time.

CACHE JUMPER CONFIGURATION

Size

JP3

JP4

JPX4

JPX5

32KB

N/A

Open

Pins 1 - 8 installed

Pins 1 - 8 installed

64KB

N/A

Open

Pins 9 - 16 installed

Pins 3 - 10 installed

128KB

N/A

Closed

Pins 1 - 8 installed

Pins 5 - 12 installed

256KB

N/A

Closed

Pins 9 - 16 installed

Pins 7 - 14 installed

512KB

N/A

Closed

Pins 1 - 8 installed

Pins 9 - 16 installed

1MB

Closed

Closed

Pins 9 - 16 installed

Pins 9 - 16 installed

CPU TYPE SELECTION

Type

JP6

JPX3

80486SX

Closed

Not installed

80486DX

Open

Installed

P23T

Open

Installed