
GIGA-BYTE TECHNOLOGY CO., LTD.

GA-486IM

Processor  CX486/AM486/UMC/80486SX/80486DX/80486DX2/80486DX4/P24D/ Pentium
           Overdrive
Processor  25/33/40/50(internal)/50/66(internal)/75(internal)/100(internal)MHz
Speed
Chip Set   UMC
Max.       128MB
Onboard
DRAM
Cache      32/64/128/256/512/1024KB
BIOS       Award
Dimensions 254mm x 218mm
I/O        32-bit VESA local bus slots (2), 32-bit PCI slots (4), green PC
Options    connector
NPU        None
Options

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Reset switch                J2       Turbo LED                  JP24

  Turbo switch                J3       Green PC LED               JP27

  Speaker                     J4       Green PC connector         JP28

  Power LED & keylock         J5       32-bit PCI slots        PC1 - PC4

  Green PC connector         JP12      32-bit VESA local bus   SL1 & SL2
                                       slots

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     P24D cache type select write            JP6           pins 2 & 3
      through                                                 closed

      P24D cache type select write            JP6           pins 1 & 2
      back                                                    closed

     Factory configured - do not             JP17             N/A
      alter

     Factory configured - do not             JP22             N/A
      alter

                DRAM CONFIGURATION

      Size            Bank 0           Bank 1

       2MB        (2) 256K x 36         NONE

       4MB        (2) 512K x 36         NONE

       4MB        (2) 256K x 36    (2) 256K x 36

       6MB        (2) 256K x 36    (2) 512K x 36

       6MB        (2) 512K x 36    (2) 256K x 36

       8MB        (2) 512K x 36    (2) 512K x 36

       8MB         (2) 1M x 36          NONE

      10MB        (2) 256K x 36     (2) 1M x 36

      10MB         (2) 1M x 36     (2) 256K x 36

      12MB        (2) 512K x 36     (2) 1M x 36

      12MB         (2) 1M x 36     (2) 512K x 36

      16MB         (2) 1M x 36      (2) 1M x 36

      16MB         (2) 2M x 36          NONE

      18MB        (2) 256K x 36     (2) 2M x 36

      18MB         (2) 2M x 36     (2) 256K x 36

      20MB        (2) 512K x 36     (2) 2M x 36

      20MB         (2) 2M x 36     (2) 512K x 36

      24MB         (2) 1M x 36      (2) 2M x 36

      24MB         (2) 2M x 36      (2) 1M x 36

      32MB         (2) 2M x 36      (2) 2M x 36

      32MB         (2) 4M x 36          NONE

      34MB        (2) 256K x 36     (2) 4M x 36

      34MB         (2) 4M x 36     (2) 256K x 36

      36MB        (2) 512K x 36     (2) 4M x 36

      36MB         (2) 4M x 36     (2) 512K x 36

      40MB         (2) 1M x 36      (2) 4M x 36

      40MB         (2) 4M x 36      (2) 1M x 36

      48MB         (2) 2M x 36      (2) 4M x 36

      48MB         (2) 4M x 36      (2) 2M x 36

      64MB         (2) 4M x 36      (2) 4M x 36

      64MB         (2) 8M x 36          NONE

      66MB        (2) 256K x 36     (2) 8M x 36

      66MB         (2) 8M x 36     (2) 256K x 36

      68MB        (2) 512K x 36     (2) 8M x 36

      68MB         (2) 8M x 36     (2) 512K x 36

      72MB         (2) 1M x 36      (2) 8M x 36

      72MB         (2) 8M x 36      (2) 1M x 36

         DRAM CONFIGURATION (CONT)

     Size          Bank 0        Bank 1

     80MB        (2) 2M x 36   (2) 8M x 36

     80MB        (2) 8M x 36   (2) 2M x 36

     96MB        (2) 4M x 36   (2) 8M x 36

     96MB        (2) 8M x 36   (2) 4M x 36

     128MB       (2) 8M x 36   (2) 8M x 36

                      CACHE CONFIGURATION

      Size          Bank 0          Bank 1           TAG

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

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

     256KB        (4) 64K x 8        NONE        (1) 32K x 8

     512KB       (4) 128K x 8        NONE        (1) 32K x 8

                        CACHE JUMPER CONFIGURATION

     Size          JP19           JP20          JP21            JP26

    128KB          Open           Open         Closed         pins 2 & 3
                                                               closed

    256KB          Open          Closed        Closed         pins 1 & 2
                                                               closed

    256KB          Open          Closed        Closed         pins 2 & 3
                                                               closed

    512KB         Closed         Closed        Closed         pins 2 & 3
                                                               closed

                    CPU TYPE CONFIGURATION

        Type                 JP3                  JP16

        Cyrix          pins 1 & 2 closed          N/A

         AMD           pins 1 & 2 closed          N/A

         UMC           pins 1 & 2 closed          N/A

       80486SX               N/A           pins 2 & 3 closed

       80486DX               N/A           pins 1 & 2 closed

        Intel          pins 1 & 2 closed          N/A

   Intel S-series      pins 3 & 4 closed          N/A

                          CPU TYPE CONFIGURATION

  Type       RN1          RN2           RN3          RN4          RN5

  Cyrix   Installed        Not          Not       Installed        Not
                       installed     installed                 installed

  AMD         Not          Not       Installed       Not           Not
          installed    installed                  installed    installed

  UMC         Not          Not       Installed       Not           Not
          installed    installed                  installed    installed

  Intel       Not      Installed        Not          Not       Installed
          installed                  installed    installed

                          CPU TYPE CONFIGURATION

          Type                     JP1                      JP13

         Cyrix              pins 1 & 2, 3 & 4               Open
                                 closed

          AMD               pins 5 & 6, 7 & 8               Open
                                 closed

          UMC               pins 5 & 6, 7 & 8               Open
                                 closed

         Intel              pins 3 & 4, 5 & 6              Closed
                                 closed

                       CPU SPEED CONFIGURATION

               Speed                              JP2

               25MHz                       pins 1 & 2 closed

               33MHz                pins 1 & 2, 3 & 4, 5 & 6 closed

               40MHz                    pins 1 & 2, 3 & 4 closed

              50iMHz                       pins 1 & 2 closed

               50MHz                       pins 5 & 6 closed

              66iMHz                pins 1 & 2, 3 & 4, 5 & 6 closed

              75iMHz                       pins 1 & 2 closed

              100iMHz               pins 1 & 2, 3 & 4, 5 & 6 closed

           CPU SPEED CONFIGURATION (80486DX4 ONLY)

        Speed                JP4                  JP23

         2x                 Closed         pins 2 & 3 closed

         3x                  Open          pins 2 & 3 closed

  BUS SPEED CONFIGURATION

  CPU speed        JP25

   <= 33MHz        Open

   > 33MHz        Closed

                         VESA DELAY CONFIGURATION

            Setting                     JP7                  JP15

     Normal card installed       pins 1 & 2 closed     pins 1 & 2 closed

  Card installed needs address   pins 2 & 3 closed     pins 2 & 3 closed
          setup time

