ATC/UNITRON COMPUTERS & COMPUTER PARTS

U6931/G/E/C

Processor

CX486M6/80486SX/80487SX/CX486M7/80486DX/80486DX2/80486DX4/ P24D/P24T

Processor Speed

25/33/40/50(internal)/50/66(internal)/75(internal/100(internal)MHz

Chip Set

OPTI

Max. Onboard DRAM

128MB

Cache

64/128/256/512KB

BIOS

Award

Dimensions

250mm x 220mm

I/O Options

32-bit VESA local bus slots (3), green PC connector

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J2

Speaker

JP38

Power LED & keylock

JP22

Green PC connector

JP39

Turbo LED

JP34

Reset switch

S1

Turbo switch

JP36

32-bit VESA local bus slots

SL1 - SL3

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

 

Monitor type select monochrome/EGA/VGA

JP1

Open

 

Monitor type select color/CGA

JP1

Closed

»

CMOS memory normal operation

JP2

Pins 2 & 3 closed

 

CMOS memory clear

JP2

Pins 1 & 2 closed

»

Factory configured - do not alter

JP6

Open

»

Factory configured - do not alter

JP7

Closed

 

P24D write back enabled

JP19

Pins 1 & 2 closed

 

P24D write through enabled

JP19

Pins 2 & 3 closed

 

CPU type select any CPU except CX486M7 2x

JP22

Open

 

CPU type select CX486M7 2x only

JP22

Closed

»

Factory configured - do not alter

JP31

Pins 2 & 3 closed

»

Factory configured - do not alter

JP41

N/A

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

2MB

(4) 256K x 9

(1) 256K x 36

None

None

2MB

None

(1) 512K x 36

None

None

4MB

(4) 1M x 9

None

None

None

4MB

None

(1) 1M x 36

None

None

8MB

(4) 1M x 9

(1) 1M x 36

None

None

8MB

None

(1) 2M x 36

None

None

16MB

(4) 4M x 9

None

None

None

16MB

None

(1) 4M x 36

None

None

16MB

(4) 1M x 9

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

16MB

None

(1) 2M x 36

(1) 2M x 36

None

32MB

(4) 4M x 9

(1) 4M x 36

None

None

32MB

None

(1) 4M x 36

(1) 4M x 36

None

64MB

None

(1) 16M x 36

None

None

64MB

(4) 4M x 9

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

128MB

None

(1) 16M x 36

(1) 16M x 36

None

DRAM JUMPER CONFIGURATION

Setting

JP5

30-pin SIMM as Bank 0

Pins 2 & 3 closed

72-pin SIMM as Bank 0

Pins 1 & 2 closed

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 (A)

(4) 32K x 8

(4) 32K x 8

(1) 16K x 8

256KB (B)

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

512KB

(4) 128K x 8

None

(1) 32K x 8

CACHE JUMPER CONFIGURATION

Size

JP8

JP27

JP28

JP43

JP44

64KB

2 & 3

Open

Open

Open

1 & 2

128KB

1 & 2

Closed

Open

Open

1 & 2

256KB (A)

2 & 3

Closed

Closed

Open

2 & 3

256KB (B)

2 & 3

Closed

Closed

Open

1 & 2

512KB

1 & 2

Closed

Closed

Closed

1 & 2

Note: Pins designated should be in the closed position.

CPU TYPE CONFIGURATION

Type

JP9

JP11

JP12

JP13

JP15

JP23

JP32

CX486M6

Closed

2 & 3

2 & 3

Open

Open

2 & 3

1 & 2

80486SX

Open

1 & 2

Open

Open

Open

2 & 3

Open

80487SX

Open

1 & 2

Open

2 & 3

Open

1 & 2, 3 & 4

Open

CX486M7

Closed

2 & 3

2 & 3

1 & 2

Open

1 & 2, 3 & 4

Open

80486DX

Open

1 & 2

Open

1 & 2

Open

1 & 2, 3 & 4

Open

80486DX2

Open

1 & 2

Open

1 & 2

Open

1 & 2, 3 & 4

Open

P24D

Open

2 & 3

Open

1 & 2

Closed

1 & 2, 3 & 4

2 & 3

80486DX4

N/A

1 & 2

1 & 2

1 & 2

N/A

1 & 2, 3 & 4

Open

P24T

Open

2 & 3

Open

1 & 2

Closed

1 & 2, 3 & 4

2 & 3

Note: Pins designated should be in the closed position. See also JP19 & JP22 in User Configurable.

CPU TYPE CONFIGURATION

Type

JP10

JP12

JP20

JP21

Non SL-enhanced

Open

Open

Open

Open

SL-enhanced

Closed

Pins 1 & 2 closed

Closed

Closed

CPU SPEED CONFIGURATION

Speed

JP16

JP17

JP18

25MHz

Open

Open

Open

33MHz

Open

Closed

Closed

40MHz

Open

Closed

Open

50iMHz

Open

Open

Open

50MHz

Open

Open

Closed

66iMHz

Open

Closed

Closed

75iMHz

Open

Open

Open

100iMHz

Open

Closed

Closed

CPU SPEED CONFIGURATION (80486DX4 ONLY)

Speed

JP30

2x

Pins 1 & 2 closed

2.5x

Pins 2 & 3 closed

3x

Open

CPU VOLTAGE CONFIGURATION

Voltage

JP29

3.45v

Pins 3 & 5, 4 & 6 closed

5v

Pins 1 & 3, 2 & 4 closed

VL BUS WAIT STATE CONFIGURATION

Wait states

JP35

0 wait states

Open

1 wait state

Closed

VL BUS SPEED CONFIGURATION

CPU speed

JP33

JP37

<= 33MHz

Pins 2 & 3 closed

Open

> 33MHz

Pins 1 & 2 closed

Closed