
ABIT COMPUTER CORPORATION

486 VESA/486 ISA

Processor        80486SX/80487SX/80486DX/80486DX2
Processor Speed  25/33/40/50(internal)/50/66(internal)MHz
Chip Set         UNI
Max. Onboard DRAM32MB
Cache            64/128/256KB
BIOS             AMI/Award
Dimensions       330mm x 218mm
I/O Options      32-bit VESA local bus slots (2)

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Power LED & keylock        JW1       Reset switch               JW5

  Speaker                    JW2       External battery           JP16

  Turbo LED                  JW3       32-bit VESA local bus    S1 & S2
                                       slots

  Turbo switch               JW4

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Factory configured - do not             JP1             Closed
      alter

     Factory configured - do not             JP2             Closed
      alter

     Factory configured - do not             JP3           pins 1 & 2
      alter                                                   closed

     Factory configured - do not             JP9             Closed
      alter

     Factory configured - do not             JP10            Closed
      alter

     Monitor type select monochrome          JP11          pins 1 & 2
                                                              closed

      Monitor type select color               JP11          pins 2 & 3
                                                              closed

     Factory configured - do not             JP12            Closed
      alter

     Factory configured - do not             JP14            Closed
      alter

     CMOS memory normal operation            JP15          pins 2 & 3
                                                              closed

      CMOS memory clear                       JP15          pins 1 & 2
                                                              closed

     Factory configured - do not             JP17            Closed
      alter

     Factory configured - do not             JP18            Closed
      alter

     Factory configured - do not             JP19            Closed
      alter

     Factory configured - do not             JP20            Closed
      alter

     Factory configured - do not             JP21            Closed
      alter

     Factory configured - do not             JP22            Closed
      alter

     Factory configured - do not             JP23            Closed
      alter

     Factory configured - do not             JP24            Closed
      alter

     Factory configured - do not             JPX4            Closed
      alter

     Factory configured - do not             JPX5            Closed
      alter

              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

      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       Max Cachable      Bank 0         Bank 1          TAG

      64KB            8MB        (4) 8K x 8     (4) 8K x 8      8K x 8

     128KB           16MB        (4) 32K x 8       NONE         8K x 8

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

       CACHE JUMPER CONFIGURATION

   Size     JPX10     JPX20     JPX30

   64KB     Closed    Open      Open

  128KB      Open    Closed     Open

  256KB      Open     Open     Closed

                          CPU SPEED CONFIGURATION

  Speed      JP4      JP28       JP29       JP31        JP32       JP33

  25MHz     1 & 2     1 & 2     1 & 2      Closed       Open      Closed

  33MHz     1 & 2     1 & 2     1 & 2      Closed      Closed      Open

  40MHz     2 & 3     2 & 3     2 & 3       Open       Closed     Closed

  50iMHz    1 & 2     1 & 2     1 & 2      Closed       Open      Closed

  50MHz     2 & 3     2 & 3     2 & 3      Closed       Open      Closed

  66iMHz    1 & 2     1 & 2     1 & 2      Closed      Closed      Open

  NotePins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

    CPU Type      JP5-JP8, JP25      JPX1          JPX2          JPX3

    80486SX         pins 1 & 2       Open         Closed        Closed
                     closed

    80487SX         pins 1 & 2       Open          Open         Closed
                     closed

  80486DX, DX2      pins 1 & 2      Closed         Open          Open
                     closed

                  VESA WAIT STATE/BUS SPEED CONFIGURATION

    CPU speed        Wait States           JP26               JP27

     < 33MHz        O wait states        pins 1 & 2         pins 1 & 2
                                          closed             closed

     > 33MHz         1 wait state        pins 2 & 3         pins 2 & 3
                                          closed             closed

