UNIDENTIFIED

486-EL

Processor

80486SX/80486DX/80486DX2/80486DX4

Processor Speed

25/33/50(internal)/66(internal)/75(internal)/100(internal)MHz

Chip Set

OPTI

Max. Onboard DRAM

16MB

Cache

8KB (on EDRAM modules)

BIOS

AMI

Dimensions

250mm x 220mm

I/O Options

32-bit VESA local bus slots (3), green PC connector

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

JP2

Reset switch

JP27

Green PC connector

JP3

Power LED & keylock

JP28

Turbo LED

JP25

Speaker

JP30

Turbo switch

JP26

32-bit VESA local bus slots

SL1 - SL3

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

CMOS memory normal operation

JP1

pins 2 & 3 closed

 

CMOS memory clear

JP1

pins 1 & 2 closed

 

Green PC IRQ select IRQ10

JP23

pins 1 & 2 closed

 

Green PC IRQ select IRQ11

JP23

pins 2 & 3 closed

 

Green PC timer select short time (1.5 minutes)

JP29

Closed

 

Green PC timer select long time (8 minutes)

JP29

Open

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

4MB

4MB

NONE

NONE

NONE

8MB

4MB

4MB

NONE

NONE

8MB

8MB

NONE

NONE

NONE

12MB

4MB

4MB

4MB

NONE

16MB

4MB

4MB

4MB

4MB

16MB

8MB

NONE

8MB

NONE

Note: This board is only compatible with EDRAM modules.

CACHE CONFIGURATION

Memory installed

Cache installed

4MB

2KB

8MB

4KB

8MB

4KB

12MB

6KB

16MB

8KB

16MB

8KB

Note: Cache is located on EDRAM modules.

CPU TYPE CONFIGURATION

Type

JP19

JP20

JP21

80486SX

Open

pins 1 & 2 closed

pins 1 & 2 closed

80486DX

Closed

pins 2 & 3 closed

pins 2 & 3 closed

80486DX2

Closed

pins 2 & 3 closed

pins 2 & 3 closed

80486DX4

Closed

pins 2 & 3 closed

pins 2 & 3 closed

CPU SPEED CONFIGURATION

Speed

JP9

JP10

JP36

25MHz

Open

Closed

pins 1 & 2 closed

33MHz

Closed

Open

pins 1 & 2 closed

50iMHz

Open

Closed

pins 1 & 2 closed

66iMHz

Closed

Open

pins 1 & 2 closed

75iMHz

Open

Closed

pins 2 & 3 closed

100iMHz

Closed

Open

pins 1 & 2 closed

CPU SPEED CONFIGURATION (80486DX4 ONLY)

Speed

JP35

2x

pins 1 & 2 closed

2.5x

pins 2 & 3 closed

3x

Open