
FIRST INTERNATIONAL COMPUTER, INC.

486SX-20 & DX-25/33 SC (REV. D)

Processor         80486SX/80486DX
Processor Speed   20/25/33MHz
Chip Set          Symphony
Max. Onboard DRAM 32MB
Cache             64/128/256/1024KB
BIOS              AMI/MR/Phoenix
Dimensions        355mm x 304mm
I/O Options       None
NPU Options       4167

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                  Location

  Speaker                     JP1       Turbo switch              JP10

  Reset switch                JP2       Turbo LED                 JP11

  Power LED & keylock         JP5

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Factory configured - do not alter        JP3           pins 2 & 3
                                                              closed

     Monitor type select monochrome           JP6             Open

      Monitor type select color                JP6            Closed

     CPU speed select iOSC/1                 JP27            Closed

     CPU speed select iOSC/2                 JP27             Open

     Cache write select 0 wait states        JP32            Closed

      Cache write select 1 wait state         JP32             Open

     Factory configured - do not alter       JP33           pins 2 & 3
                                                              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

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

      20MB        (4) 1M x 9      (4) 4M 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) 32K x 8

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

     1024KB      (4) 128K x 8    (4) 128K x 8    (1) 128K x 8

               CACHE JUMPER CONFIGURATION (CONT)

   Size       JP22       JP23       JP24       JP25       JP26

   64KB       1 & 2      1 & 2      1 & 2      1 & 2      Open

   128KB      2 & 3      1 & 2      1 & 2      1 & 2     Closed

   256KB      2 & 3      2 & 3      1 & 2      1 & 2      Open

    1MB       2 & 3      2 & 3      2 & 3      2 & 3      Open

  Note: Pins designated should be in the closed position.

             CACHE JUMPER CONFIGURATION (CONT)

   Size      JP28      JP34       JP35      JP36      JP37

   64KB     Closed     1 & 2     2 & 3     2 & 3     2 & 3

  128KB      Open      Open      1 & 2     1 & 2     1 & 2

  256KB     Closed     2 & 3     2 & 3     2 & 3     2 & 3

   1MB      Closed     2 & 3     2 & 3     2 & 3     2 & 3

  Note: Pins designated should be in the closed position.

             CACHE JUMPER CONFIGURATION (CONT)

   Size      JP38      JP39       JP40      JP41      JP42

   64KB      Open      2 & 3     2 & 3      Open     2 & 3

  128KB     Closed     Open      1 & 2     Closed    2 & 3

  256KB      Open      2 & 3     2 & 3      Open     2 & 3

   1MB       Open      2 & 3     2 & 3      Open     2 & 3

  Note: Pins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

       Type               JP12              JP13               JP14

      80486SX             Open           pins 2 & 3            Open
                                           closed

      80486DX            Closed          pins 1 & 2           Closed
                                           closed

