
NORTHGATE COMPUTER SYSTEMS, INC.

NORTHGATE ENERGY STAR LX400A/G REV. 3.1

Processor       80486SX/80487SX/80486DX/80486DX2
Processor Speed 25/33/40/50(internal)/50/66(internal)MHz
Chip Set        SIS
Max. Onboard    32MB
DRAM
Cache           64/128/256KB
BIOS            AMI
Dimensions      254mm x 220mm
I/O Options     32-bit VESA local bus slots (2), PS/2 mouse port, green PC
                connector
NPU Options     None

[Image]

                                CONNECTIONS

  Purpose                Location     Purpose                  Location

  Turbo LED                 J3        Flash LED                   J10

  Turbo switch              J4        PS/2 mouse port             J11

  Speaker                   J5        Green PC connector          J12

  Reset switch              J6        Green PC connector          J28
                                      (monitor)

  Power LED & keylock       J7        32-bit VESA local bus    SL1 & SL2
                                      slots

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Factory configured - do not             JP1              Open
      alter

     Monitor type select color               JP2             Closed

      Monitor type select monochrome          JP2              Open

     On board mouse enabled                  JP12          pins 1 & 2
                                                              closed

      On board mouse disabled                 JP12          pins 2 & 3
                                                              closed

     Factory configured - do not             JP13          pins 2 & 3
      alter                                                   closed

     Power good signal detect from           JP14          pins 1 & 2
      power supply                                            closed

      Power good signal detect from           JP14          pins 2 & 3
      board                                                   closed

     Factory configured - do not             JP21             Open
      alter

     Factory configured - do not             JP22             Open
      alter

     Factory configured - do not             JP23             Open
      alter

     Factory configured - do not            JP100             Open
      alter

              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

      20MB        (4) 1M x 9      (4) 4M x 9

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

                    CACHE CONFIGURATION

     Size          Bank 0         Bank 1          TAG

     64KB        (4) 8K x 8     (4) 8K x 8    (1) 8K x 8

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

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

                 CACHE JUMPER CONFIGURATION

   Size       SR1       SR2       SR3       SR4       SR5

   64KB      2 & 3     2 & 3     1 & 2     1 & 2     1 & 2

  128KB      1 & 2     1 & 2     2 & 3     2 & 3     1 & 2

  256KB      2 & 3     2 & 3     2 & 3     2 & 3     2 & 3

  Note: Pins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

       Type               JP6               JP7                JP8

      80486SX             Open              Open            pins 2 & 3
                                                              closed

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

      80486DX            Closed          pins 1 & 2         pins 1 & 2
                                           closed             closed

     80486DX2            Closed          pins 1 & 2         pins 1 & 2
                                           closed             closed

                   CPU SPEED CONFIGURATION

        Speed                JP10                 JP11

        25MHz          pins 2 & 3 closed   pins 2 & 3 closed

        33MHz          pins 2 & 3 closed   pins 1 & 2 closed

        40MHz          pins 1 & 2 closed   pins 2 & 3 closed

       50iMHz          pins 2 & 3 closed   pins 2 & 3 closed

        50MHz          pins 1 & 2 closed   pins 1 & 2 closed

       66iMHz          pins 2 & 3 closed   pins 1 & 2 closed

                VESA WAIT STATE CONFIGURATION

     Wait states             JP24                 JP26

    0 wait states      pins 1 & 2 closed   pins 1 & 2 closed

    1 wait state       pins 2 & 3 closed   pins 2 & 3 closed

                   BUS SPEED CONFIGURATION

      CPU speed              JP25                 JP27

      <= 33MHz         pins 1 & 2 closed   pins 1 & 2 closed

       > 33MHz         pins 2 & 3 closed   pins 2 & 3 closed

