FOREX COMPUTER CORPORATION

386/486 CACHE SYSTEM BOARD

Processor

80386DX/CX486DLC/80486SX/80487SX/80486DX/80486DX2

Processor Speed

20/25/33/40/50(internal)/50/66(internal) MHz

Chip Set

Forex

Max. onboard DRAM

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

32-bit local bus slot

NPU Options

80387DX

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

JP2

Speaker

JP10

Reset switch

JP8

Turbo switch

JP15

Power LED & keylock

JP9

32-bit Local bus slot

S1

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Factory configured - do not alter

JP5

N/A

»

CMOS memory normal operation

JP6

Closed

 

CMOS memory clear

JP6

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

5MB

(4) 256K x 9

(4) 1M x 9

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

20MB

(4) 1M x 9

(4) 4M x 9

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

(2) 8K x 8

CACHE JUMPER CONFIGURATION

Size

JP8A

JP8B

JP8C

JP8E

JP8F

64KB

pins 2 & 3

pins 1 & 2

pins 1 & 2

pins 2 & 3

pins 1 & 2

128KB

pins 1 & 2

pins 2 & 3

pins 2 & 3

pins 1 & 2

pins 1 & 2

256KB

pins 2 & 3

pins 1 & 2

pins 1 & 2

pins 1 & 2

pins 2 & 3

Note:Pins designated should be in the closed position.

CPU SPEED CONFIGURATION

Speed

JP7A

JP7B

JP7C

JP7D

20MHz

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

25MHz

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

33MHz

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

40MHz

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

50MHz

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

66MHz

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

80MHz

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

CPU TYPE CONFIGURATION

Type

W1B

W1A - W1G

W2A

W2A

W2C - W2H

80386DX

pins 2 & 3

pins 2 & 3

pins 2 & 3

pins 2 & 3

pins 2 & 3

CX486DLC

pins 2 & 3

pins 2 & 3

pins 2 & 3

pins 2 & 3

pins 2 & 3

80486

pins 1 & 2

pins 1 & 2

pins 1 & 2

pins 1 & 2

pins 1 & 2

Notes:Pins designated should be in the closed position.

80486 CPU TYPE CONFIGURATION

Type

JP12

JP13

JP30

80486SX

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

80487SX

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

80486DX

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

80486DX2

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed