
NORTHGATE COMPUTER SYSTEMS, INC.

486E

Processor            80486SX/80487SX/80486DX/80486DX2
Processor Speed      20/25/33/50/50(internal)/66(internal)MHz
Chip Set             OPTI
Max. Onboard DRAM    128MB
Cache                64/128/256KB
BIOS                 AMI
Dimensions           330mm x 218mm
I/O Options          None
NPU Options          4167

[Image]

                                CONNECTIONS

  Purpose                Location       Purpose              Location

  IDE interface LED    J4 & J5 pins     Turbo LED         J5 pins 8 & 18
                         10 & 20

  Speaker             J5 pins 1 - 4     Reset switch      J5 pins 9 & 19

  Turbo switch        J5 pins 7 & 17    Power LED &       J5 pins 11 - 15
                                        keylock

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Monitor type select color                JP5            Closed

      Monitor type select monochrome           JP5             Open

     EISA EXRDY to CHRDY conversion           JP7             Open
      disabled

      EISA EXRDY to CHRDY conversion           JP7            Closed
      enabled

                           DRAM CONFIGURATION

          Size                  Bank 0                  Bank 1

          4MB                 (4) 1M x 9                 NONE

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

          16MB                (4) 4M x 9                 NONE

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

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

          64MB                (4) 16M x 9                NONE

         128MB                (4) 16M x 9             (4) 16M x 9

  Note:When upgrading to 128MB, you must increase the cache to 256KB.

                            CACHE CONFIGURATION

    Size       Bank 0     Bank 1     TAG (U39)    TAG (U41)    TAG (U50)

    64KB      (4) 8K x   (4) 8K x    (1) 8K x 8   (1) 16K x     (1) 16K x
                 8          8                         1            1

   128KB       (4) 32K     NONE      (1) 8K x 8   (1) 16K x     (1) 16K x
                x 8                                   1            1

   256KB       (4) 32K    (4) 32K    (1) 32K x    (1) 16K x     (1) 16K x
                x 8        x 8           8            1            1

                             CACHE JUMPER CONFIGURATION

  Size      RNA1         RNA2         RNB1         RNB2         RNC1        RNC2

  64KB    Installed   Installed        Not          Not          Not         Not
                                   installed    installed    installed    installed

  128KB      Not          Not      Installed    Installed        Not         Not
          installed   installed                              installed    installed

  256KB      Not          Not          Not          Not      Installed    Installed
          installed   installed    installed    installed

                          CPU TYPE CONFIGURATION

     Type           RBA             RBB             RBC            W4

   80486SX       Installed      Not installed   Not installed    Closed

   80487SX      Not installed    Installed      Not installed     Open

   80486DX      Not installed   Not installed    Installed        Open

   80486DX2     Not installed   Not installed    Installed        Open

                          CPU SPEED CONFIGURATION

    Speed           JP1            JP2            JP3            JP4

    20MHz        pins 2 & 3     pins 1 & 2     pins 1 & 2     pins 2 & 3
                  closed         closed         closed          closed

    25MHz        pins 1 & 2     pins 1 & 2     pins 1 & 2     pins 2 & 3
                  closed         closed         closed          closed

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

    50iMHz       pins 1 & 2     pins 1 & 2     pins 2 & 3     pins 2 & 3
                  closed         closed         closed          closed

    50MHz        pins 1 & 2     pins 2 & 3     pins 2 & 3     pins 1 & 2
                  closed         closed         closed          closed

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

