UNIDENTIFIED

486SI4

Processor         80486SX/80487SX/80486DX/80486DX2
Processor Speed   20/25/33/50/66(internal)MHz
Chip Set          C & T
Max. Onboard DRAM 32MB
Cache             64/128/256KB
BIOS              AMI/C & T
Dimensions        330mm x 218mm
I/O Options       32-bit external video card slot
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                 Location    Purpose                   Location

  Turbo LED                  J3       Reset switch                 J6

  Turbo switch               J4       Power LED & keylock          J7

  Speaker                    J5       32-bit external video        S1
                                      card

  Note:32-bit external video card slot may not be present on some board
  revisions.

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

  »   Local bus data size select 32            J8            pins 1 & 2
      bits                                                    closed

      Local bus data size select 16            J8            pins 2 & 3
      bits                                                    closed

  »   Factory configured - do not alter        JP1             Open

  »   Monitor type select color                JP2            Closed

      Monitor type select monochrome           JP2             Open

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

  »   Factory configured - do not alter        JP4           pins 2 & 3
                                                              closed

  »   Factory configured - do not alter        JP5            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) 4M x 9      (4) 1M 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) 8K x 8

                        CACHE JUMPER CONFIGURATION

    Sizer          SR1            SR2            SR3             SR4

    64KB        pins 1 & 2     pins 1 & 2     pins 2 & 3      pins 2 & 3
                 closed          closed         closed         closed

    128KB       pins 2 & 3     pins 2 & 3     pins 2 & 3      pins 1 & 2
                 closed          closed         closed         closed

    256KB       pins 2 & 3     pins 2 & 3     pins 2 & 3      pins 2 & 3
                 closed          closed         closed         closed

             CACHE JUMPER CONFIGURATION (CON’T)

   Size       SR5       SR6       SR7       SR8       SR9

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

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

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

  Note: Pins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

       Type               JP6               JP7                JP8

      80486SX            Open              Open             pins 2 & 3
                                                             closed

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

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