DASH COMPUTER, INC.

486WB WRITEBACK-CACHE SYSTEM BOARD

Processor         80486SX/80486DX
Processor Speed   33/50MHz
Chip Set          OPTI
Max. Onboard DRAM 32MB
Cache             64/256KB
BIOS              AMI
Dimensions        330mm x 220mm
I/O Options       32-bit external memory card slot
NPU Options       4167

[Image]

                                CONNECTIONS

  Purpose                 Location     Purpose                  Location

  External battery           J11       32-bit external             S1
                                       memory card

  Power LED & keylock        J23       Reset switch               SW1

  Speaker                    J24       Turbo switch               SW2

  Turbo LED                 JP11

                        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

  »   Factory configured - do not alter        JP7             open

  »   CPU speed select OSC/2                   JP8           pins 2 & 3
                                                              closed

      CPU speed select OSC/1                   JP8           pins 1 & 2
                                                              closed

              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) 256K x 9    (4) 1M x 9

      8MB        (4) 1M x 9      (4) 1M x 9

     16MB        (4) 4M x 9         NONE

     20MB        (4) 1M x 9      (4) 4M x 9

     32MB        (4) 4M x 9      (4) 4M x 9

                        CPU JUMPER CONFIGURATION

    CPU             JP3                 JP4                  JP5

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

  80486SX          open                 open          pins 2 & 3 closed

                        CACHE JUMPER CONFIGURATION

     Size           JP6            JP9           JP10           JP12

     64KB        pins 2 & 3        open          open           open
                   closed

    128KB        pins 1 & 2        open         closed         closed
                   closed

    256KB        pins 2 & 3        open         closed         closed
                   closed

                    CACHE CONFIGURATION

     Size          Cache         Location         TAG

     64KB        (8) 8K x 8    Banks 0 & 1       NONE

     128KB      (4) 32K x 8      Banks 0      (1) 8K x 8

     256KB      (8) 32K x 8    Banks 0 & 1    (1) 8K x 8