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





50/33/25/20MHZ MAINBOARD

UNIDENTIFIED

50/33/25/20MHZ MAINBOARD

Processor

80486SX/80487SX/80486DX/80486DX2

Processor Speed

20/25/33/40/50 (Internal) /50/66 (Internal)

Chip Set

C & T

Max. onboard DRAM

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

None

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

Power LED & keylock

J17

External battery

J20

Speaker

J18

Turbo switch

J21

Reset switch

J19

Turbo LED

J22

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

Monitor type select monochrome

JP3

Open

 

Monitor type select color

JP3

Closed

CMOS memory normal operation

JP5

Pins 1 & 2 closed

 

CMOS memory clear

JP5

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

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

Max Cachable

Bank 0

Bank 1

TAG

64KB

16MB

(4) 8K x 8

(4) 8K x 8

(1) 8K x 8

128KB

32MB

(4) 32K x 8

NONE

(1) 8K x 8

256KB

64MB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

CACHE JUMPER CONFIGURATION

Size

JP24

JP25

64KB

Open

Open

128KB

Pins 1 & 2 closed

Pins 1 & 2 closed

256KB

Pins 2 & 3 closed

Pins 2 & 3 closed

CPU SPEED CONFIGURATION

Speed

JP21

80486SX/20MHz

Pins 5 & 6 closed

80486SX/25MHz

Pins 1 & 2, 5 & 6 closed

80486SX/33MHz

Pins 1 & 2, 3 & 4 closed

80487SX/20MHz

Pins 5 & 6 closed

80486DX/25MHz

Pins 1 & 2, 5 & 6 closed

80486DX/33MHz

Pins 1 & 2, 3 & 4 closed

80486DX/40MHz

Pins 5 & 6 closed

80486DX/50MHz

Pins 3 & 4 closed

80486DX2/50i MHz

Pins 1 & 2, 5 & 6 closed

80486DX2/66i MHz

Pins 1 & 2, 3 & 4 closed

CPU TYPE CONFIGURATION

TYPE

JP9

JP11

JP12

JP13

80486SX/20MHz

Pins 2 & 3 closed

Open

Pins 2 & 3 closed

Pins 2 & 3 closed

80486SX/25MHz

Pins 1 & 2 closed

Open

Pins 2 & 3 closed

Pins 2 & 3 closed

80486SX/33MHz

Pins 1 & 2 closed

Open

Pins 2 & 3 closed

Pins 2 & 3 closed

80487SX/20MHz

Pins 2 & 3 closed

Closed

Pins 2 & 3 closed

Pins 1 & 2 closed

80486DX/25MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX/33MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX/40MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX/50MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX2/50i MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX2/66i MHz

Pins 1 & 2 closed

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed