NORTHGATE COMPUTER SYSTEMS, INC.
================================

   486ZXP

   Processor        80486SX/80486DX/80486DX2                      
   Processor Speed  16/20/25/33/50(internal)/66(internal)MHz      
   Chip Set         OPTI                                          
   Max. Onboard     32MB                                          
   DRAM             
   Cache            64/256KB                                      
   BIOS             AMI                                           
   Dimensions       330mm x 218mm                                 
   I/O Options      Parallel port, serial ports (2), floppy drive 
                    interface, IDE interface                      
   NPU Options      4167                                          

<gopher://bitreich.org/I/th99/m/M-O/30602-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose           | Location | Purpose          | Location |
   |-------------------+----------+------------------+----------|
   | Parallel port     |    J1    | Turbo LED        |   JP3    |
   |-------------------+----------+------------------+----------|
   | Serial port 1     |    J2    | Reset switch     |   JP4    |
   |-------------------+----------+------------------+----------|
   | Serial port 2     |    J3    | Speaker          |   JP5    |
   |-------------------+----------+------------------+----------|
   | Floppy drive      |    J4    | IDE interface    |   JP6    |
   | interface         |          | LED              |          |
   |-------------------+----------+------------------+----------|
   | IDE interface     |    J5    | External battery |   JP22   |
   |-------------------+----------+------------------+----------|
   | Power LED &       |   JP2    |                  |          |
   | keylock           |          |                  |          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |               Function               | Jumper |  Position  |
   |--------------------------------------+--------+------------|
   |   | Monitor type select color        |  JP1   |   Closed   |
   |---+----------------------------------+--------+------------|
   |   | Monitor type select monochrome   |  JP1   |    Open    |
   |---+----------------------------------+--------+------------|
   |>> | Parallel port IRQ select         |  JP19  | pins 2 & 3 |
   |   | LPT1/IRQ7                        |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Parallel port IRQ select         |  JP19  | pins 1 & 2 |
   |   | LPT2/IRQ5                        |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | I/O ports enabled                |  JP20  | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | I/O ports disabled               |  JP20  | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Battery type select internal     |  JP21  | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Battery type select external     |  JP21  | 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         |
   |--------------+----------------------+----------------------|
   |     5MB      |     (4) 256K x 9     |      (4) 1M x 9      |
   |--------------+----------------------+----------------------|
   |     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      |
   |------------------------------------------------------------|
   | Note:Systems being used as file servers should not use the |
   | 5MB or 20MB configurations.                                |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    CACHE CONFIGURATION                     |
   |------------------------------------------------------------|
   |            Size            |            Bank 0             |
   |----------------------------+-------------------------------|
   |            64KB            |          (8) 64K x 1          |
   |----------------------------+-------------------------------|
   |           256KB            |          (8) 64K x 4          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 CACHE JUMPER CONFIGURATION                 |
   |------------------------------------------------------------|
   |   Size    |    JP7     |    JP11    |   JP12   |   JP13    |
   |-----------+------------+------------+----------+-----------|
   |   64KB    |    Open    |    Open    |   Open   |   Open    |
   |-----------+------------+------------+----------+-----------|
   |   256KB   |   Closed   |   Closed   |   Open   |  Closed   |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   CPU TYPE CONFIGURATION                   |
   |------------------------------------------------------------|
   |   Type    |        JP8        |        JP9        |  JP10  |
   |-----------+-------------------+-------------------+--------|
   |  80486SX  |       Open        | pins 2 & 3 closed |  Open  |
   |-----------+-------------------+-------------------+--------|
   |  80486DX  | pins 1 & 2 closed | pins 1 & 2 closed | Closed |
   |-----------+-------------------+-------------------+--------|
   | 80486DX2  | pins 2 & 3 closed | pins 1 & 2 closed | Closed |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   CPU SPEEDCONFIGURATION                   |
   |------------------------------------------------------------|
   | Speed  |    JP14    |    JP15    |    JP16    |    JP17    |
   |--------+------------+------------+------------+------------|
   | 16MHz  | pins 2 & 3 | pins 2 & 3 | pins 2 & 3 | pins 1 & 2 |
   |        |   closed   |   closed   |   closed   |   closed   |
   |--------+------------+------------+------------+------------|
   | 20MHz  | pins 2 & 3 | pins 1 & 2 | pins 2 & 3 | pins 1 & 2 |
   |        |   closed   |   closed   |   closed   |   closed   |
   |--------+------------+------------+------------+------------|
   | 25MHz  | pins 2 & 3 | pins 2 & 3 | pins 1 & 2 | pins 2 & 3 |
   |        |   closed   |   closed   |   closed   |   closed   |
   |--------+------------+------------+------------+------------|
   | 33MHz  | pins 2 & 3 | pins 1 & 2 | pins 1 & 2 | pins 2 & 3 |
   |        |   closed   |   closed   |   closed   |   closed   |
   |--------+------------+------------+------------+------------|
   | 50iMHz | pins 2 & 3 | pins 2 & 3 | pins 1 & 2 | pins 2 & 3 |
   |        |   closed   |   closed   |   closed   |   closed   |
   |--------+------------+------------+------------+------------|
   | 66iMHz | pins 2 & 3 | pins 1 & 2 | pins 1 & 2 | pins 2 & 3 |
   |        |   closed   |   closed   |   closed   |   closed   |
   +------------------------------------------------------------+