
MICRO-STAR INTERNATIONAL CO., LTD.

MS-4131 VLB 486 AL2

Processor        80486SX/80487SX/80486DX/80486DX2
Processor Speed  25/33/40/50(internal)/50/66(internal)MHz
Chip Set         ALI
Max. Onboard DRAM112MB
Cache            128/256KB
BIOS             AMI
Dimensions       254mm x 218mm
I/O Options      32-bit VESA local bus slots (3)
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                  Location     Purpose                 Location

  External battery            JB        32-bit VESA Local bus      S2
                                        slot

  32-bit VESA Local bus       S1        32-bit VESA Local bus      S3
  slot                                  slot

                  PIN OUT CONFIGURATION

          Connector                      JFP

           Keylock                pins 1 & 2 closed

          Power LED               pins 3 & 5 closed

          Turbo LED              pins 12 & 13 closed

        Turbo switch           pins 15, 16, & 17 closed

            Reset                pins 19 & 20 closed

           Speaker            pins 7, 8, 9, & 10 closed

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Factory configured - do not             JC1           pins 1 & 2
      alter                                                   closed

     Factory configured - do not             JC2           pins 1 & 2
      alter                                                   closed

     Factory configured - do not             JC3           pins 1 & 2
      alter                                                   closed

     Factory configured - do not             JC5             Closed
      alter

     Factory configured - do not             JC7           pins 1 & 2
      alter                                                   closed

     CPU PQFP not installed                  JC8             Closed

      CPU PQFP installed                      JC8              Open

     Factory configured - do not             JC9              N/A
      alter

     Factory configured - do not             JC10             Open
      alter

     Monitor type select monochrome          JP1           pins 1 & 2
                                                              closed

      Monitor type select color               JP1           pins 2 & 3
                                                              closed

     Factory configured - do not             JP4              N/A
      alter

                            CACHE CONFIGURATION

      Size            Bank 0          Bank 1                TAG

      128KB        (4) 32K x 8         NONE          (1)8K x 8/(1)16K x
                                                       8/(1)32K x 8

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

                  CACHE JUMPER CONFIGURATION

        Size                 JS1                  JS2

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

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

        256KB          pins 1 & 2 closed   pins 1 & 2 closed

                    CPU TYPE CONFIGURATION

        Type                 JC4                  JC6

       80486SX         pins 1 & 2 closed         Open

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

       80486DX         pins 2 & 3 closed   pins 2 & 3 closed

      80486DX2         pins 2 & 3 closed   pins 2 & 3 closed

                          CPU SPEED CONFIGURATION

   Speed         JK1         JK2        JK3          JK4           JP2

   25MHz      3 & 7 and    pins 1 &   pins 1 &      Closed       pins 1 &
                4 & 8         2          2                          2

   33MHz      1 & 2 and    pins 1 &   pins 1 &      Closed       pins 1 &
                4 & 8         2          2                          2

   40MHz      1 & 5 and    pins 2 &   pins 2 &      Closed       pins 2 &
                2 & 6         3          3                          3

  50i MHz     3 & 7 and    pins 1 &   pins 1 &      Closed       pins 1 &
                4 & 8         2          2                          2

   50MHz       pins 2 &    pins 2 &   pins 2 &       Open        pins 2 &
                  6           3          3                          3

  66i MHz     1 & 2 and    pins 1 &   pins 1 &      Closed       pins 1 &
                4 & 8         2          2                          2

  Note:Pins designated should be in the closed position.

                VESA WAIT STATE/BUS SPEED CONFIGURATION

    CPU speed        Wait states     JP4/pins 1 & 2    JP4/pins 3 & 4

       33MHz       0 wait states         Open              Open

      > 33MHz       1 wait state         Closed            Closed

                      DRAM CONFIGURATION

      Size          Bank 0          Bank 1          Bank 2

      1MB        (4) 256K x 9        None            None

      4MB            None         (1) 1M x 36        None

      4MB            None            None        (1) 1M x 36

      4MB         (4) 1M x 9         None            None

      5MB        (4) 256K x 9     (1) 1M x 36        None

      5MB        (4) 256K x 9        None        (1) 1M x 36

      8MB            None         (1) 1M x 36    (1) 1M x 36

      8MB            None         (1) 2M x 36        None

      8MB            None            None        (1) 2M x 36

      9MB        (4) 256K x 9     (1) 2M x 36        None

      9MB        (4) 256K x 9        None        (1) 2M x 36

      12MB        (4) 1M x 9      (1) 2M x 36        None

      12MB        (4) 1M x 9         None        (1) 2M x 36

      16MB        (4) 4M x 9         None            None

      16MB        (4) 4M x 9      (1) 1M x 36        None

      16MB           None         (1) 2M x 36    (1) 2M x 36

      16MB        (4) 4M x 9         None        (1) 1M x 36

      24MB        (4) 4M x 9      (1) 2M x 36        None

      24MB        (4) 4M x 9         None        (1) 2M x 36

      32MB           None         (1) 4M x 36        None

      32MB           None            None        (1) 4M x 36

      33MB       (4) 256K x 9     (1) 4M x 36        None

      33MB       (4) 256K x 9        None        (1) 4M x 36

      36MB        (4) 1M x 9      (1) 4M x 36        None

      36MB        (4) 1M x 9         None        (1) 4M x 36

      48MB        (4) 4M x 9      (1) 4M x 36        None

      48MB        (4) 4M x 9         None        (1) 4M x 36

                  DRAM CONFIGURATION (CONT.)

      Size          Bank 0          Bank 1          Bank 2

      64MB           None         (1) 8M x 36        None

      64MB           None         (1) 4M x 36    (1) 4M x 36

      64MB           None            None        (1) 8M x 36

      65MB       (4) 256K x 9        None        (1) 8M x 36

      65MB       (4) 256K x 9     (1) 8M x 36        None

      68MB        (4) 1M x 9      (1) 8M x 36        None

      68MB        (4) 1M x 9         None        (1) 8M x 36

      88MB        (4) 4M x 9         None        (1) 8M x 36

      88MB        (4) 4M x 9      (1) 8M x 36        None

      96MB           None         (1) 8M x 36    (1) 4M x 36

      97MB       (4) 256K x 9     (1) 8M x 36    (1) 4M x 36

     100MB        (4) 1M x 9      (1) 8M x 36    (1) 4M x 36

     112MB        (4) 4M x 9      (1) 8M x 36    (1) 4M x 36

