FIRST INTERNATIONAL COMPUTER, INC.

486-20/25/33/50SC (REV. A)

Processor

80486SX/80486DX

Processor Speed

20/25/33/50MHz

Chip Set

Symphony

Max. Onboard DRAM

32MB

Cache

64/128/256/1024KB

BIOS

AMI

Dimensions

330.2mm x 218.4mm

I/O Options

None

NPU Options

4167

CONNECTIONS

Purpose

Location

Purpose

Location

Turbo switch

JP12

Speaker

JP18

Turbo LED

JP14

Power LED & keylock

JP19

Reset switch

JP17

   

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

Factory configured - do not alter

JP4

pins 2 & 3 closed

»

CPU speed select iOSC/2

JP5/6

Off

 

CPU speed select iOSC/1

JP5/6

On

»

Monitor type select monochrome

JP5/8

Off

 

Monitor type select color

JP5/8

On

»

Factory configured - do not alter

JP20

pins 1 & 2 closed

»

Factory configured - do not alter

JP21

pins 1 & 2 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) 1M x 9

(4) 256K x 9

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

20MB

(4) 4M x 9

(4) 1M 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) 32K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

1024KB

(4) 128K x 8

(4) 128K x 8

(1) 128K x 8

CACHE JUMPER CONFIGURATION

Size

JP3

JP6

JP7

JP8

JP9

JP10

JP11

JP13

JP15

JP16

64KB

1 & 2

2 & 3

1 & 2

2 & 3

1 & 2

1 & 2

1 & 2

2 & 3

2 & 3

2 & 3

128KB

1 & 2

1 & 2

Open

1 & 2

1 & 2

1 & 2

2 & 3

open

1 & 2

1 & 2

256KB

1 & 2

2 & 3

2 & 3

2 & 3

1 & 2

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

1024KB

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

2 & 3

Note:Pins designated should be in the closed position.

CACHE SWITCH CONFIGURATION

Size

JP5/3

JP5/4

JP5/5

JP5/7

64KB

Off

Off

Off

On

128KB

On

On

On

Off

256KB

Off

Off

Off

On

1024KB

Off

Off

Off

On

CPU TYPE CONFIGURATION

Type

JP2

JP5/1

JP5/2

80486SX

pins 2 & 3 closed

Off

Off

80486DX

pins 1 & 2 closed

On

On