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J-MARK COMPUTER CORPORATION

JET-486 CACHE 486-33/486SX-25

Processor

80486SX/80486DX

Processor Speed

25/33MHz

Chip Set

ETEQ

Max. Onboard DRAM

32MB

Cache

64/256KB

BIOS

AMI

Dimensions

330mm x 220mm

I/O Options

32-bit external memory card slot

NPU Options

80487SX/4167

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J1

Power LED & keylock

J5

Reset switch

J2

Speaker

J6

Turbo switch

J3

32-bit external memory card

S1

Turbo LED

J4

 

 

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Factory configured - do not alter

JP1

N/A

»

Monitor type select monochrome

JP2

Open

 

Monitor type select color

JP2

Closed

»

CMOS memory normal operation

JP3

Closed

 

CMOS memory clear

JP3

Open

»

Factory configured - do not alter

JP4

N/A

»

Factory configured - do not alter

JP11

N/A

»

Factory configured - do not alter

JP12

N/A

»

Factory configured - do not alter

JP13

N/A

»

Factory configured - do not alter

JP14

N/A

»

Factory configured - do not alter

JP21

N/A

»

Factory configured - do not alter

JP23

N/A

»

Factory configured - do not alter

JP24

N/A

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) 1 M x 9

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

32MB

(4) 4M x 9

(4) 4M x 9

CACHE CONFIGURATION

Size

Bank 0

TAG (U22)

TAG (U23)

64KB

(8) 8K x 8

(1) 16K x 4

NONE

256KB

(8) 32K x 8

(1) 16K x 4

(1) 16K x 4

CACHE JUMPER CONFIGURATION

Size

JP5

JP6

JP7

JP8

JP22

64KB

Open

Open

2 & 3

2 & 3

Open

256KB

Closed

Closed

1 & 2

1 & 2

Closed

Note: Pins designated should be in the closed position.

CPU TYPE CONFIGURATION

Type

JP9

JP10

JP15

JP16

80486SX

pins 1 & 2 closed

Closed

pins 1 & 2 closed

Open

80486SX + 80487SX

pins 1 & 2 closed

Closed

pins 1 & 2 closed

Open

80486DX

pins 1 & 2 closed

Closed

pins 2 & 3 closed

Closed

NPU JUMPER CONFIGURATION

Type

JP17

JP18

JP19

JP20

80487SX

Open

Open

Open

Open

4167

Closed

Closed

Closed

Closed

Note: In order to use the Weitek 4167, a daughter board must be installed in the CPU socket. You would then insert the NPU and CPU into the daughter board.