UNIDENTIFIED

U486

Processor

80486SX/80487SX/80486DX

Processor Speed

33/50MHz

Chip Set

UMC

Video Chip Set

None

Maximum Onboard Memory

32MB

Maximum Video Memory

None

Cache

64/128/256KB

BIOS

AMI

Dimensions

254mm x 218mm

I/O Options

None

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J3

Turbo switch

J10

Speaker

J8

Turbo LED

J11

Power LED & keylock

J9

Reset switch

J12

USER CONFIGURABLE SETTINGS

Function

Label

Position

»

Battery type select internal

J1

Closed

 

Battery type select external

J1

Open

»

Keyboard clock select synchronous

J5

Pins 2 & 3 closed

 

Keyboard clock select asynchronous

J5

Pins 1 & 2 closed

»

Monitor type select color

J6

Closed

 

Monitor type select monochrome

J6

Open

»

CMOS memory normal operation

J13

Pins 1 & 2 closed

 

CMOS memory clear

J13

Pins 2 & 3 closed

»

Turbo sped disabled

JP1

Closed

 

Turbo speed enabled

JP1

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

(1) 32K x 8

Note: The location of banks 0 & 1 are unidentified.

CACHE JUMPER CONFIGURATION

Size

W1

W2

W3

W5

W6

W7

W8

W9

64KB

1 & 2

Open

1 & 2

1 & 2

Open

Open

Open

Open

128KB

2 & 3

1 & 2

1 & 2

2 & 3

Closed

Open

Open

Closed

256KB

1 & 2

2 & 3

2 & 3

2 & 3

Closed

Closed

Closed

Closed

Note: Pins designated should be in the closed position.

CPU CLOCK MODE SELECTION

Speed

W10

1x

Open

2x

Closed

CPU TYPE SELECTION

Type

W11

W12

80486SX

Pins 2 & 3 closed

Open

80487SX

Pins 1 & 2, 3 & 4 closed

Pins 2 & 3 closed

80486DX

Pins 1 & 2, 3 & 4 closed

Pins 1 & 2 closed