J-MARK COMPUTER CORPORATION

J-756A

Device Type

Mainboard

Processor

Pentium Pro

Processor Speed

150/180/200MHz

Chip Set

Intel 440FX

Maximum Onboard Memory

512MB (EDO supported)

Cache

256/512KB (located on Pentium Pro CPU)

BIOS

Unidentified

Dimensions

330mm x 218mm

I/O Options

32-bit PCI slots (4), floppy drive interface, green PC connector, IDE interfaces (2), parallel port, PS/2 mouse interface, serial ports (2), IR connector, USB connectors (2)

CONNECTIONS

Purpose

Location

Purpose

Location

IDE interface LED

C1

Serial port 1

J7

Turbo LED

C2

Floppy drive interface

J8

Reset switch

C3

IDE interface 2

J9

Speaker

C4

CPU fan power

J11

Green PC connector

C5

External battery

J19

Turbo switch

C6

IR connector

JP1

Power LED & keylock

C7

USB connector 1

JP2

Serial port 2

J4

USB connector 2

JP3

Parallel port

J5

32-bit PCI slots

PC1 – PC4

IDE interface 1

J6

   

USER CONFIGURABLE SETTINGS

Function

Label

Position

»

CMOS memory normal operation

J19

Pins 2 & 3 closed

 

CMOS memory clear

J19

Pins 3 & 4 closed

 

Battery type select external

J19

Open

 

Flash BIOS voltage select 12v

JP15

Pins 2 & 3 closed

 

Flash BIOS voltage select 5v

JP15

Pins 1 & 2 closed

»

CMOS memory normal operation

JP23

Open

 

CMOS memory clear

JP23

Closed

 

PS/2 mouse IRQ enabled

JP25

Closed

 

PS/2 mouse IRQ disabled

JP25

Open

SIMM CONFIGURATION

Size

Bank 0

Bank 1

8MB

(2) 1M x 36

None

16MB

(2) 2M x 36

None

16MB

(2) 1M x 36

(2) 1M x 36

24MB

(2) 2M x 36

(2) 1M x 36

32MB

(2) 4M x 36

None

32MB

(2) 2M x 36

(2) 2M x 36

40MB

(2) 4M x 36

(2) 1M x 36

48MB

(2) 4M x 36

(2) 2M x 36

64MB

(2) 8M x 36

None

SIMM CONFIGURATION (CON’T)

Size

Bank 0

Bank 1

64MB

(2) 4M x 36

(2) 4M x 36

72MB

(2) 8M x 36

(2) 1M x 36

80MB

(2) 8M x 36

(2) 2M x 36

96MB

(2) 8M x 36

(2) 4M x 36

128MB

(2) 8M x 36

(2) 8M x 36

128MB

(2) 16M x 36

None

136MB

(2) 16M x 36

(2) 1M x 36

144MB

(2) 16M x 36

(2) 2M x 36

160MB

(2) 16M x 36

(2) 4M x 36

192MB

(2) 16M x 36

(2) 8M x 36

256MB

(2) 16M x 36

(2) 16M x 36

256MB

(2) 32M x 36

None

264MB

(2) 32M x 36

(2) 1M x 36

272MB

(2) 32M x 36

(2) 2M x 36

288MB

(2) 32M x 36

(2) 4M x 36

320MB

(2) 32M x 36

(2) 8M x 36

384MB

(2) 32M x 36

(2) 16M x 36

512MB

(2) 32M x 36

(2) 32M x 36

Note: Board accepts EDO memory.

CACHE CONFIGURATION

Note: 256KB/512KB cache is located on the Pentium Pro CPU.

CPU SPEED SELECTION

CPU speed

Clock speed

Multiplier

JP17

JP18

JP19

JP20

JP21

JP22

150MHz

60MHz

2.5x

Open

Closed

Open

Closed

Closed

Closed

180MHz

60MHz

3x

Open

Closed

Closed

Open

Closed

Closed

200MHz

66MHz

3x

Closed

Open

Closed

Open

Closed

Closed

CPU VOLTAGE SELECTION

Voltage

JP12/pins 1 & 2

JP12/pins 3 & 4

JP12/pins 5 & 6

JP12/pins 7 & 8

Auto

Open

Open

Open

Open

2.1v

Open

Open

Open

Closed

2.2v

Open

Open

Closed

Open

2.3v

Open

Open

Closed

Closed

2.4v

Open

Closed

Open

Open

2.5v

Open

Closed

Open

Closed

2.6v

Open

Closed

Closed

Open

2.7v

Open

Closed

Closed

Closed

2.8v

Closed

Open

Open

Open

2.9v

Closed

Open

Open

Closed

3.0v

Closed

Open

Closed

Open

3.1v

Closed

Open

Closed

Closed

3.2v

Closed

Closed

Open

Open

3.3v

Closed

Closed

Open

Closed

3.4v

Closed

Closed

Closed

Open

3.5v

Closed

Closed

Closed

Closed