HwMuseum | Index

UNIDENTIFIED

486LC25/33

Processor

80486DX

Processor Speed

25/33MHz

Chip Set

Intel

Max. Onboard DRAM

16MB

Cache

128/256KB

BIOS

AMI/Award/Phoenix

Dimensions

335mm x 277mm

I/O Options

None

NPU Options

4167

CONNECTIONS

Purpose

Location

Purpose

Location

Power LED & keylock

J1

Reset switch

J5

Turbo switch

J3

Turbo LED

J6

Speaker

J4

External battery

JB2

Note:Pin one locations are unidentified.

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

DRAM speed select 80ns or 100ns (for 25Mhz CPU)

JP4

pins 2 & 3 closed

 

DRAM speed select 60ns or 80ns (for 33MHz CPU)

JP4

pins 1 & 2 closed

»

Factory configured - do not alter

SW1/1

N/A

»

Operating system select other than SCO UNIX Open Desktop

SW1/2

Off

 

Operating system select SCO UNIX Open Desktop

SW1/2

On

»

Monitor type select color

SW1/5

On

 

Monitor type select monochrome

SW1/5

Off

»

DRAM 32-bit access enabled

SW1/6

On

 

DRAM 32-bit access disabled

SW1/6

Off

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

1MB

(4) 256K x 9

NONE

NONE

NONE

2MB

(4) 256K x 9

(4) 256K x 9

NONE

NONE

3MB

(4) 256K x 9

(4) 256K x 9

(4) 256K x 9

NONE

4MB

(4) 256K x 9

(4) 256K x 9

(4) 256K x 9

(4) 256K x 9

4MB

(4) 1M x 9

NONE

NONE

NONE

8MB

(4) 1M x 9

(4) 1M x 9

NONE

NONE

12MB

(4) 1M x 9

(4) 1M x 9

(4) 1M x 9

NONE

16MB

(4) 1M x 9

(4) 1M x 9

(4) 1M x 9

(4) 1M x 9

DRAM JUMPER CONFIGURATION

Size

JP1

JP2

JP3

1MB

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

2MB

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

3MB

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

4MB 1

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

4MB 2

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

8MB

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

12MB

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

16MB

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

Note 1 :Use this setting when (4) 256K x 9 SIMMs are populating all four banks.

Note 2 :Use this setting when (4) 1M x 9 SIMMs are populating Bank 0.

CACHE CONFIGURATION

Size

Bank 0

Bank 1

128KB

(4) 32K x 8

NONE

256KB

(4) 32K x 8

(4) 32K x 8

CACHE SWITCH CONFIGURATION

Function

Switch SW1

Position

»

SRAM cache enabled

SW1/3

On

 

SRAM cache disabled

SW1/3

Off

»

DRAM installed between 12MB and 16MB is cached

SW1/4

On

 

DRAM installed between 12MB and 16MB is not cached

SW1/4

Off

BIOS CONFIGURATION

Size

JP5

SW1/7

27256

pins 1 & 2 closed

Off

27512

pins 2 & 3 closed

On