
BIOSTAR MICROTECH INTERNATIONAL CORPORATION

MB-1420/1425/1433PB REV. A

MB-1420/1425/1433PV REV. A

Processor        80486SX/80487SX/P23T/80486DX/80486DX2
Processor Speed  20/25/33/50(internal)/50/66(internal)MHz
Chip Set         Unidentified
Max. Onboard DRAM32MB
Cache            None
BIOS             AMI
Dimensions       254mm x 218mm
I/O Options      None
NPU Options      4167

[Image]

                                CONNECTIONS

  Purpose                   Location   Purpose                   Location

  Power LED & keylock         J1       Turbo switch                JP6

  Speaker                     J2       External battery            JP8

  Turbo LED                   J3       Reset switch                SW1

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Monitor type select color               JP5             Closed

      Monitor type select monochrome          JP5              Open

     CMOS memory normal operation            JP7           pins 2 & 3
                                                              closed

      CMOS memory clear                       JP7           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) 1M x 9     (4) 256K x 9

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

      16MB        (4) 4M x 9         NONE

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

                          CPU TYPE CONFIGURATION

          Type               JP9        JP10         JP11         JP12

     80486SX (PQFP)          Open       Open        Closed        Open

      80486SX (PGA)          Open       Open        2 & 3         Open

         80487SX            2 & 3       1 & 2       Closed        Open

     80486SX (PQFP) &       2 & 3       1 & 2       Closed       1 & 2
         80487SX

  80486SX (PQFP) & P23T     2 & 3       1 & 2       Closed       2 & 3

     80486SX (PQFP) &       1 & 2       1 & 2       Closed       2 & 3
       80486DX/DX2

         80486DX            1 & 2       1 & 2       Closed        Open

        80486DX2            1 & 2       1 & 2       Closed        Open

  Note: Pins designated should be in the closed position.

                        KEYBOARD BIOS CONFIGURATION

     Type           JP1            JP2            JP3            JP4

    8042 (23       Closed          Open          Open            Open
     pins)

    8042 (24        Open          Closed         Open            Open
     pins)

    8042 (27        Open           Open         Closed           Open
     pins)

    8042 (30        Open           Open          Open           Closed
     pins)

