
AMERICAN MEGATRENDS, INC.

ENTERPRISE-IV EISA VLB

Processor      80486SX/80487SX/80486DX/ODP486SX/80486DX2/Pentium Overdrive
Processor      25/33/50(internal)/50/66(internal)MHz
Speed
Chip Set       AMI
Max. Onboard   256MB
DRAM
Cache          256KB
BIOS           AMI
Dimensions     330mm x 218mm
I/O Options    32-bit VESA local bus slots (2), floppy drive interface,

               IDE interface, parallel port, serial ports (2)
NPU Options    None

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                 Location

  Serial port 1                J2       Power LED & keylock       J34

  Serial port 2                J3       Turbo switch              J39

  Parallel port                J4       Speaker                   J40

  IDE interface LED            J5       Reset switch              J41

  Floppy drive interface       J6       Turbo LED                 J42

  IDE interface                J9       32-bit VESA Local          S1
                                        bus slot

  PS/2 mouse                  J11       32-bit VESA Local          S2
                                        bus slot

                        USER CONFIGURABLE SETTINGS

              Function                  Jumper/Switch        Position

     Factory configured - do not            J10                N/A
      alter

     Factory configured - do not            J21                N/A
      alter

     CPU low priority                       J31             pins 1 & 2
                                                              closed

      CPU high priority                      J31             pins 2 & 3
                                                              closed

     Factory configured - do not            J38                N/A
      alter

     Factory configured - do not       SW1/switch 1            Off
      alter

     Monitor type select               SW1/switch 2            Off
      monochrome

      Monitor type select color         SW1/switch 2            On

                            DRAM CONFIGURATION

     Size          Bank 0         Bank 1         Bank 2         Bank 3

      1MB         (1) 256K x       None           None           None
                     36

      2MB         (1) 256K x     (1) 256K x       None           None
                     36             36

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

      6MB         (1) 256K x     (1) 256K x    (1) 1M x 36       None
                     36             36

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

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

     12MB        (1) 1M x 36    (1) 1M x 36    (1) 1M x 36       None

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

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

     18MB         (1) 256K x     (1) 256K x    (1) 4M x 36       None
                     36             36

     20MB        (1) 1M x 36    (1) 4M x 36       None           None

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

     32MB        (1) 4M x 36    (1) 4M x 36       None           None

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

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

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

     64MB        (1) 4M x 36    (1) 4M x 36    (1) 4M x 36   (1) 4M x 36

     64MB        (1) 16M x 36      None           None           None

     128MB       (1) 16M x 36   (1) 16M x 36      None           None

     192MB       (1) 16M x 36   (1) 16M x 36    (1) 16M x        None
                                                   36

     256MB       (1) 16M x 36   (1) 16M x 36    (1) 16M x    (1) 16M x 36
                                                   36

         CPU SPEED CONFIGURATION

    Speed       J12      J13       J14

    25MHz      Open      Open     Open

    33MHz      Open     Closed    Open

   50i MHz     Open      Open     Open

    50MHz      Closed    Open     Closed

   66i MHz     Open     Closed    Open

                          CPU TYPE CONFIGURATION

      PGA CPU              PQFP CPU           J15       J16        J43

        None           80486SX,80486DX        N/A       N/A       Open

      ODP486SX,        80486SX,80486DX        1&2,     pins 2    Closed
  80487SX, ODP586SX                           3&4       & 3

      ODP486SX,              None             1&2,     pins 2      N/A
  80487SX, ODP586SX                           3&4       & 3

  80486DX, 80486DX2          None             1&2,     pins 1      N/A
                                              3&4       & 2

  80486DX, 80486DX2    80486SX,80486DX        1&2,     pins 1    Closed
                                              3&4       & 2

      80486SX                None            pins 2     N/A        N/A
                                              & 3

      80486SX          80486SX,80486DX       pins 2     N/A      Closed
                                              & 3

  Note:Pins designated should be in the closed position.

                      SERIAL PORT INTERRUPT SELECTION

     Port 1 (J2)         Port 2 (J3)          J22               J23

          IRQ4             IRQ3           pins 2 & 3        pins 1 & 2
                                            closed            closed

           IRQ3             IRQ4           pins 1 & 2        pins 2 & 3
                                            closed            closed

