UNIDENTIFIED

486/25 MAINBOARD

Processor         80486SX
Processor Speed   25MHz
Chip Set          Unidentified
Max. Onboard DRAM None (8MB or 16MB on riser card)
Cache             None (8KB is on the CPU)
BIOS              Award
Dimensions        330mm x 225mm
I/O Options       None
NPU Options       80387DX

[Image]

                                CONNECTIONS

  Purpose                   Location   Purpose                   Location

  External battery           CON1      Speaker                    CON5

  Turbo LED                  CON2      Power LED & keylock        CON6

  Turbo switch               CON3      Riser Card                  S1

  Reset switch               CON4

                        USER CONFIGURABLE SETTINGS

              Function                  Jumper/Switch        Position

  »   Battery type select external           JP1             pins 2 & 3
                                                              closed

      Battery type select internal           JP1             pins 1 & 2
                                                              closed

  »   Monitor type select                    JP2             pins 2 & 3
      monochrome                                              closed

      Monitor type select color              JP2             pins 1 & 2
                                                              closed

  »   Power good from mainboard              JP3             pins 2 & 3
                                                              closed

      Power good from power supply           JP3             pins 1 & 2
                                                              closed

                                                                   [Image]

                 DRAM CONFIGURATION

       Size            Bank 1            Bank 2

       1MB           (36) 41256           NONE

       2MB           (36) 41256           (1) 41256

       4MB           (36) 41000           NONE

       8MB           (36) 41000        (36) 41000

                     MEMORY CARD CONFIGURATION

  Select    SW1/1    SW1/2     SW1/3     SW1/4    SW1/5     SW1/6

   1MB       On        On       On        On        On        On

   2MB       Off       On       On        On        On       Off

   4MB       Off      Off       On        On       Off        On

   8MB       Off      Off       Off       On       Off       Off

  Note: SW1 is located on the mainboard.

[Image]

                            DRAM CONFIGURATION

     Size         Bank 0         Bank 1         Bank 2         Bank 3

     1MB        (4) 256K x 9      NONE           NONE           NONE

     2MB        (4) 256K x 9   (4) 256K x 9      NONE           NONE

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

     4MB        (4) 1M x 9        NONE           NONE           NONE

     8MB        (4) 1M x 9     (4) 1M x 9        NONE           NONE

     16MB       (4) 1M x 9     (4) 1M x 9     (4) 1M x 9     (4) 1M x 9

  Note: This may be SIMM or SIP

                     MEMORY CARD CONFIGURATION

  Select    SW1/1    SW1/2     SW1/3     SW1/4    SW1/5     SW1/6

   1MB       On        On       On        On        On        On

   2MB       Off       On       On        On        On       Off

   4MB       Off      Off       On        On        On       Off

   4MB       Off      Off       On        On       Off        On

   8MB       Off      Off       Off       On       Off       Off

   16MB      Off      Off       Off       Off      Off       Off

  Note: SW1 is located on the mainboard.