
AMERICAN MEGATRENDS, INC.

386 AT MARK II SYSTEM MOTHERBOARD

Processor              80386
Processor Speed        16/20/25/33MHz
Chip Set               Unidentified
Video Chip Set         None
Maximum Onboard Memory 16MB (8MB on external memory card)
Maximum Video Memory   None
Cache                  None
BIOS                   AMI
Dimensions             355mm x 304mm
I/O Options            External memory card
NPU Options            80387/3167

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                   Location

  Turbo LED                   J1       Power LED & keylock         J8

  Reset switch                J2       External battery            J9

  Speaker                     J7       External memory card        SL1

                        USER CONFIGURABLE SETTINGS

               Function                    Label           Position

     Factory configured - do not           J26          Unidentified
      alter

      Factory configured - do not          SW/1               Off
      alter

      Monitor type select color            SW/2               On

      Monitor type select monochrome       SW/2               Off

                            DRAM CONFIGURATION

         Size                    Bank 0                    Bank 1

          1MB                  (36) 41256                   None

          1MB                     None                  (4) 256K x 9

          2MB                  (36) 41256               (4) 256K x 9

          4MB                 (36) 411000                   None

          4MB                     None                   (4) 1M x 9

          5MB                  (36) 41256                (4) 1M x 9

          5MB                 (36) 411000               (4) 256K x 9

          8MB                 (36) 411000                (4) 1M x 9

         16MB                     None                   (4) 4M x 9

  Note: Board will accept 441000 chips but the configuration was not
  available.

                         DRAM JUMPER CONFIGURATION

       Bank 0 chips             Bank 1 chips                 J27

        Installed               Not installed          Pins 1 & 2, 3 & 4
                                                            closed

      Not installed               Installed            Pins 2 & 3, 4 & 5
                                                            closed

          41256                    256K/1M             Pins 1 & 2, 3 & 4
                                                            closed

          411000                   256K/1M             Pins 2 & 3, 4 & 5
                                                            closed

          441000                Any chip type          Pins 1 & 2, 3 & 4
                                                            closed

      Any chip type                  4M                Pins 2 & 3, 4 & 5
                                                            closed

             DRAM CONFIGURATION

     Size          Bank 2        Bank 3

      8MB        (18) 411000   (18) 411000

                         DRAM SWITCH CONFIGURATION

     Mark II         BASE board        SW/1         SW/2         SW/3
     memory           memory

      640KB           1 bank           Off           On           On

      896KB           2 banks           On           On           On

     1664KB           1 bank           Off          Off           On

     1920KB           2 banks           On          Off           On

     3712KB           1 bank           Off           On           On

     3968KB           2 banks           On           On           On

     4736KB           1 bank           Off           On           Off

     4992KB           2 banks           On           On           Off

     7808KB           1 bank           Off          Off           On

     8064KB           2 banks           On          Off           On

      N/A*            2 banks           On          Off           Off

  Note: * = Memory configuration in the 14MB & 15MB region is enabled.
  For all other configurations, the region is disabled.

