J-MARK COMPUTER CORPORATION

JET-486

Processor            80486SX/80487SX/80486DX/80486DX2
Processor Speed      20/25/33/50(internal)/50/66(internal)MHz
Chip Set             OPTI
Max. Onboard DRAM    32MB
Cache                64/128/256KB
BIOS                 AMI/Award
Dimensions           220mm x 220mm
I/O Options          None
NPU Options          None

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                  Location

  External battery             J1       Turbo LED                 JP11

  Speaker                     J17       Reset switch               SW1

  Power LED & keylock         J18       Turbo switch               SW2

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

  »   CMOS memory normal operation             JP1           pins 2 & 3
                                                              closed

      CMOS memory clear                        JP1           pins 1 & 2
                                                              closed

  »   Monitor type select color                JP2            Closed

      Monitor type select monochrome           JP2             Open

              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

      17MB        (4) 4M x 9     (4) 256K x 9

      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) 8K x 8

     256KB      (4) 32K x 8    (4) 32K x 8    (1) 32K x 8

                        CACHE JUMPER CONFIGURATION

     Size           JP3            JP4            JP6            JP7

     64KB        pins 2 & 3        Open          Open            Open
                  closed

    128KB        pins 1 & 2       Closed        Closed           Open
                  closed

    256KB        pins 2 & 3       Closed        Closed          Closed
                  closed

                          CPU TYPE CONFIGURATION

       Type                JP8               JP9               JP10

      80486SX           pins 2 & 3          Open               Open
                         closed

      80487SX           pins 1 & 2         Closed           pins 1 & 2
                         closed                               closed

      80486DX           pins 1 & 2         Closed           pins 2 & 3
                         closed                               closed

     80486DX2           pins 1 & 2         Closed           pins 2 & 3
                         closed                               closed