
GIGA-BYTE TECHNOLOGY CO., LTD

GA-386UM 33/40 MAIN BOARD

Processor         80386DX
Processor Speed   33/40MHz
Chip Set          OPTI
Max. Onboard DRAM 32MB
SRAM Cache        64/128/256KB
BIOS              AMI
Dimensions        220mm x 260mm
I/O Options       None
NPU Options       80387/3167

[Image]

                                CONNECTIONS

  Purpose                 Location     Purpose                 Location

  Power LED & keylock        J1        Turbo switch               J4

  Speaker                    J2        Turbo LED                  J5

  Reset switch               J3        External battery           J11

  Note:Board may be supplied with either a PGA (socketed) or PQFP
  (surface mounted) CPU.

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     NPU absent                               J7              open

      NPU present                              J7             closed

     Monitor type select color                J8             closed

      Monitor type select monochrome           J8              open

     CMOS memory normal operation             J9            pins 2 & 3
                                                              closed

      CMOS memory clear                        J9            pins 1 & 2
                                                              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

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

                    SRAM CONFIGURATION

     Size        Cache SRAM      Location         TAG

     64KB        (8) 8K x 8    Banks 0 & 1    (1) 8K x 8

     128KB      (4) 32K x 8       Bank 0      (1) 8K x 8

     256KB      (8) 32K x 8    Banks 0 & 1    (1) 32K x 8

                         SRAM JUMPER CONFIGURATION

   Size         WC1         WC2         WC3         WC4           WC5

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

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

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

