Processor

80486SX/80486DX2 (on external CPU/Cache module)

Processor Speed

25/66I MHz (only with external CPU/Cache module)

Chip Set

AST

Max. Onboard DRAM

64MB

SRAM Cache

256KB (on external CPU/Cache module)

BIOS

AST

Dimensions

254mm x 338mm

I/O Options

Bus mouse port, CPU/Cache upgrade module, floppy drive interface, IDE interface, LAN module, parallel port, serial port (2), VGA port

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

Serial port 2 (COM2)

J12

Floppy drive interface

J24

Parallel port

J13

External speaker

J27

Bus mouse port

J14

Fan power

J28

LAN module

J15 & J16

Front panel switches & LEDs

J29

Serial port 1 (COM1)

J17

Feature connector

J46

VGA port

J18

CPU/Cache upgrade module

J50, J51, J52, J53

VGA pass-through

J19

IDE interface LED

J100

IDE interface

J22

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

Factory configured - do not alter

E1

open

»

Factory configured - do not alter

E2

pins 2 & 3 closed

»

Parallel port interrupt select IRQ7

E5

pins 2 & 3 closed

Parallel port interrupt select IRQ5

E5

pins 1 & 2 closed

»

CMOS memory normal operation

E6

open

CMOS memory clear

E6

closed

»

VGA port enabled

SW1/switch 1

closed

VGA port disabled

SW1/switch 1

open

»

Password check enabled

SW1/switch 2

open

Password check disabled

SW1/switch 2

closed

»

Factory configured - do not alter

SW1/switch 3

open

»

Factory configured - do not alter

SW1/switch 4

open

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

2MB

(1) 256K x 36

(1) 256K x 36

NONE

NONE

4MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

4MB

(1) 1M x 36

NONE

NONE

NONE

8MB

(1) 1M x 36

(1) 1M x 36

NONE

NONE

16MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

16MB

(1) 4M x 36

NONE

NONE

NONE

32MB

(1) 4M x 36

(1) 4M x 36

NONE

NONE

64MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

VRAM CONFIGURATION

Size

VRAM

512KB

(4) 44256

CONNECTIONS

Purpose

Location

CPU/Cache upgrade module

J50, J51, J52, J53

Note: Connections are on the back side of the module and correspond to the connector with the same label on the motherboard.

CACHE CONFIGURATION

Size

Cache SRAM

256KB

(8) 256K x 1

CPU/CACHE MODULE TYPE CONFIGURATION

Module Type

Jumper E4

Jumper E5

Jumper E7

Jumper E8

CPU only

open

closed

closed

closed

Cache only

closed

open

open

open

»

CPU and Cache

closed

closed

open

open

Note:These settings are given for information only and should not be changed.

CPU SPEED CONFIGURATION

Internal

External

Jumper E1

Jumper E3

Jumper E6

25MHz

25MHz

closed

closed

open

33MHz

33MHz

open

closed

open

50MHz

25MHz

closed

closed

open

»

66MHz

33MHz

open

closed

open

Note:These settings are given for information only and should not be changed.

CPU TYPE CONFIGURATION

CPU Type

Jumper E2

Jumper E9

Jumper E10

Jumper E11

»

80486DX2

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

closed

ODP486SX

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

closed

80486DX

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

closed

80487SX

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

closed

80486SX

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

open

None

open

open

open

open

Note:These settings are given for information only and should not be changed.