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)

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  IDE interface LED           C1       Serial port 1               J7

  Turbo LED                   C2       Floppy drive                J8
                                       interface

  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     Clock   Multiplier    JP17     JP18     JP19    JP20     JP21     JP22
  speed    speed

  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     JP12/pins 3    JP12/pins 5   JP12/pins 7 &
                   & 2            & 4            & 6              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