
UNIDENTIFIED

452S

Processor        80486SX/80487SX/80486DX/80486DX2/Pentium Overdrive
Processor Speed  25/33/40/50(internal)/50/66(internal)MHz
Chip Set         SIS
Max. Onboard DRAM32MB
Cache            64/128/256KB
BIOS             AMI
Dimensions       254mm x 220mm
I/O Options      32-bit VESA local bus slots (3)
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Power LED & keylock         J1       Reset switch                J5

  Speaker                     J2       External battery           JP13

  Turbo LED                   J3       32-bit VESA local bus   SL1 - SL3
                                       slots

  Turbo switch                J4

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Monitor type select monochrome          JP12             Open

      Monitor type select color               JP12            Closed

     CMOS memory normal operation            JP14             Open

      CMOS memory clear                       JP14            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

      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

                            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) 8K x 8

       256KB          (4) 32K x 8      (4) 32K x 8     (1) 16K x 8 or (1)
                                                            32K x 8

                  CACHE JUMPER CONFIGURATION

        Size                 JP9                  JP10

        64KB                 Open                 Open

        128KB               Closed         pins 1 & 2 closed

        256KB               Closed         pins 2 & 3 closed

                          CPU TYPE CONFIGURATION

        Type                JP1              JP2                JP3

       80486SX             Open           pins 2 & 3           Open
                                            closed

       80487SX            Closed          pins 1 & 2         pins 2 & 3
                                            closed            closed

     80486DX/DX2          Closed          pins 1 & 2         pins 1 & 2
                                            closed            closed

  Pentium Overdrive       Closed          pins 1 & 2         pins 2 & 3
                                            closed            closed

         CPU SPEED CONFIGURATION

   Type      JS1        JS2       JS3

  25MHz      Open      Open     Closed

  33MHz     Closed     Open      Open

  40MHz     Closed    Closed     Open

  50iMHz     Open      Open     Closed

  50MHz      Open     Closed     Open

  66iMHz    Closed     Open      Open

      VESA WAIT STATE CONFIGURATION

     Wait states             JP16

    0 wait states     pins 1 & 2 closed

    1 wait state      pins 2 & 3 closed

         BUS SPEED CONFIGURATION

      CPU speed              JP15

      <= 33MHz        pins 1 & 2 closed

       > 33MHz        pins 2 & 3 closed

