AMERICAN MEGATRENDS, INC.

486 GEMINI

Processor

80486DX

Processor Speed

25/33MHz

Chip Set

C & T

Max. Onboard DRAM

20MB

Cache

64KB

BIOS

AMI

Dimensions

355.6mm x 304mm

I/O Options

32-bit external memory card slot

NPU Options

3167

CONNECTIONS

Purpose

Location

Purpose

Location

Turbo LED

J1

Power LED & keylock

J8

Reset switch

J2

External battery

J9

Speaker

J7

32-bit external memory card

S1

USER CONFIGURABLE SETTINGS

Function

Switch

Position

»

Factory configured - do not alter

SW1/1

Off

»

Monitor type select monochrome

SW1/2

Off

 

Monitor type select color

SW1/2

On

 

Note : Cache is factory installed and is not configurable. The size and location of cache and tag are unidentified.

DRAM CONFIGURATION

Size

Bank 0

Bank 1

1MB

(36) 41256

NONE

1MB

NONE

(4) 256K x 9

2MB

(36) 41256

(4) 256K x 9

4MB

(36) 411000

NONE

4MB

NONE

(4) 1M x 9

5MB

(36) 41256

(4) 1M x 9

5MB

(36) 411000

(4) 256K x 9

8MB

(36) 411000

(4) 1M x 9

16MB

NONE

(4) 4M x 9

17MB

(36) 41256

(4) 4M x 9

20MB

(36) 411000

(4) 4M x 9

Note : There were two versions of this board made, one that had 1MB of DIPP DRAM installed and one that had 4MB of DIPP DRAM installed. The 1MB version could be upgraded by the factory to support 4MB of DIPP DRAM.

DRAM JUMPER CONFIGURATION

Size

J26

J27

1MB

Open

pins 1 & 2 and 3 & 4 closed

1MB

Open

pins 2 & 3 and 4 & 5 closed

2MB

Open

pins 1 & 2 and 3 & 4 closed

4MB

Open

pins 1 & 2 and 3 & 4 closed

4MB

Open

pins 2 & 3 and 4 & 5 closed

5MB

Open

pins 1 & 2 and 3 & 4 closed

5MB

Open

pins 2 & 3 and 4 & 5 closed

8MB

Open

pins 2 & 3 and 4 & 5 closed

16MB

pins 1 & 2 closed

pins 2 & 3 and 4 & 5 closed

17MB

pins 1 & 2 closed

pins 1 & 2 and 3 & 4 closed

20MB

pins 1 & 2 closed

pins 1 & 2 and 3 & 4 closed