
BIOSTAR MICROTECH INTERNATIONAL CORPORATION

MB-1425/33/40/50UCV-A

Processor        CX486S/80486SX/80487SX/80486DX/ODP486SX/80486DX2/

                 Pentium Overdrive
Processor Speed  25/33/40/50(internal)/50/66(internal)MHz
Chip Set         Biostar
Max. Onboard DRAM64MB
Cache            32/64/128/256KB
BIOS             AMI
Dimensions       330mm x 218mm
I/O Options      32-bit VESA local bus slots (3)
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  External battery           JP8       Power LED & keylock       JP15E

  5V ground                 JP15A      Speaker                   JP15F

  Turbo switch              JP15B      32-bit VESA Local bus       V1
                                       slot

  Reset switch              JP15C      32-bit VESA Local bus       V2
                                       slot

  Turbo LED                 JP15D      32-bit VESA Local bus       V3
                                       slot

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     CMOS memory normal operation            JP8           pins 2 & 3
                                                              closed

      CMOS memory clear                       JP8           pins 3 & 4
                                                              closed

     Power good signal detect from           JP11          pins 1 & 2
      power supply                                            closed

      Power good signal detect from           JP11          pins 2 & 3
      board                                                   closed

     One CPU (PQFP or PGA) on board          JP12          pins 1 & 2
      installed                                               closed

      Two CPUs (enabled PGA and               JP12          pins 2 & 3
      disabled PQFP) on board installed                       closed

     Monitor type select color               JP14          pins 2 & 3
                                                              closed

      Monitor type select monochrome          JP14          pins 1 & 2
                                                              closed

     Add on card select normal               JP28          pins 1 & 2
      operation                                               closed

      Add on card select Weitek 9000          JP28          pins 2 & 3
      VGA card installed                                      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      (4) 4M x 9

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

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

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

      64MB        (4) 16M x 9        NONE

                            CACHE CONFIGURATION

     Size        Max Cachable      Bank 0        Bank 1          TAG

     32KB             8MB        (4) 8K x 8       NONE        (1) 8K x 8

     64KB            16MB        (4) 8K x 8    (4) 8K x 8     (1) 8K x 8

     128KB           32MB        (4) 32K x 8      NONE        (1) 8K x 8

     256KB           64MB        (4) 32K x 8   (4) 32K x 8    (1) 16K x 8

     256KB           64MB        (4) 32K x 8   (4) 32K x 8    (1) 32K x 8

                        CACHE JUMPER CONFIGURATION

    Size         JP5        JP6          JP7          JP9         JP10

    32KB       pins 2 &     Open        Open          Open        Open
                  3

    64KB       pins 1 &     Open        Open         Closed       Open
                  2

    128KB      pins 2 &   pins 2 &     Closed        Closed       Open
                  3          3

    256KB      pins 1 &   pins 1 &     Closed        Closed      pins 2 &
                  2          2                                      3

    256KB      pins 1 &   pins 1 &     Closed        Closed      pins 1 &
                  2          2                                      2

  Note:Pins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

           Type                     JP16                    JP17

          CX486S                    Open              pins 2 & 3 closed

          80486SX                   Open              pins 2 & 3 closed

          80487SX             pins 2 & 3 closed      pins 1 & 2 and 3 & 4
                                                           closed

          80486DX             pins 1 & 2 closed      pins 1 & 2 and 3 & 4
                                                           closed

         ODP486SX             pins 2 & 3 closed      pins 1 & 2 and 3 & 4
                                                           closed

         80486DX2             pins 1 & 2 closed      pins 1 & 2 and 3 & 4
                                                           closed

     Pentium Overdrive        pins 1 & 2 closed      pins 1 & 2 and 3 & 4
                                                           closed

               CPU SPEED CONFIGURATION

   Speed      JP21       JP22      JP23       JP27

   25MHz     Closed      Open     Closed      Open

   33MHz     Closed     Closed     Open       Open

   40MHz      Open       Open     Closed     Closed

  50i MHz    Closed      Open     Closed      Open

   50MHz      Open      Closed     Open      Closed

  66i MHz    Closed     Closed     Open       Open

                       VESA BUS SPEED CONFIGURATION

      Mode         JP19     JP20      JP25      JP26      JP29      JP30
                                     (V2)      (V1)      (V3)      (V2 &
                                                                    V3)

   Synchronous     pins 1   pins 1   pins 1    pins 1    pins 1    pins 1
                    & 2      & 2      & 2       & 2       & 2       & 2

  Asynchronous     pins 2   pins 2   pins 2    pins 2    pins 2    pins 2
                    & 3      & 3      & 3       & 3       & 3       & 3

  Note:Pins designated should be in the closed position.

  When V2 & V3 are used at the same time, JP25 must be left open.

