DELL COMPUTER CORPORATION
=========================

   Precision 486SX/25, Precision 486DX/33

   Processor             80486SX/80487SX/80486DX                  
   Processor Speed       25/33MHz                                 
   Chip Set              OPTI                                     
   Max. Onboard DRAM     32MB                                     
   Cache                 64/256KB                                 
   BIOS                  AMI                                      
   Dimensions            330mm x 218mm                            
   I/O Options           None                                     
   NPU Options           None                                     

<gopher://bitreich.org/I/th99/m/C-D/30908-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose            | Location  | Purpose        | Location |
   |--------------------+-----------+----------------+----------|
   | Reset switch       |    J9     | Speaker        |   J21    |
   |--------------------+-----------+----------------+----------|
   | External battery   |    J18    | Power LED &    |   J22    |
   |                    |           | keylock        |          |
   |--------------------+-----------+----------------+----------|
   | Turbo switch       |    J20    |                |          |
   |------------------------------------------------------------|
   | Note:Although there is a 4167 socket on the board, it is   |
   | not supported. (As per the manufacturer)                   |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |               Function               | Jumper |  Position  |
   |--------------------------------------+--------+------------|
   |>> | Battery select internal          |   W1   |   Closed   |
   |---+----------------------------------+--------+------------|
   |   | Battery select external          |   W1   |    Open    |
   |---+----------------------------------+--------+------------|
   |>> | CMOS memory normal operation     |   W2   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | CMOS memory clear                |   W2   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | CPU speed select ATCLK/4         |   W3   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | CPU speed select ATCLK/6         |   W3   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |   W8   |    Open    |
   |   | alter                            |        |            |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |   W9   |    Open    |
   |   | alter                            |        |            |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |  W10   |    Open    |
   |   | alter                            |        |            |
   |---+----------------------------------+--------+------------|
   |>> | Monitor type select color        |  W12   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Monitor type select monochrome   |  W12   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Factory test disabled            |  W13   |    Open    |
   |---+----------------------------------+--------+------------|
   |   | Factory test enabled             |  W13   | 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) 1M x 9     |    (4) 256K x 9    |
   |------------------+--------------------+--------------------|
   |       8MB        |     (4) 1M x 9     |     (4) 1M x 9     |
   |------------------+--------------------+--------------------|
   |       16MB       |     (4) 4M x 9     |        NONE        |
   |------------------+--------------------+--------------------|
   |       20MB       |     (4) 4M x 9     |    (4) 256K x 9    |
   |------------------+--------------------+--------------------|
   |       32MB       |     (4) 4M x 9     |     (4) 1M x 9     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    CACHE CONFIGURATION                     |
   |------------------------------------------------------------|
   |            Size            |            Bank 0             |
   |----------------------------+-------------------------------|
   |            64KB            |          (8) 8K x 8           |
   |----------------------------+-------------------------------|
   |           256KB            |          (8) 32K x 8          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 CACHE JUMPER CONFIGURATION                 |
   |------------------------------------------------------------|
   | Size  |       W8        |       W9        |      W18       |
   |-------+-----------------+-----------------+----------------|
   | 64KB  |   pins 2 & 3    |   pins 2 & 3    |   pins 2 & 3   |
   |       |     closed      |     closed      |     closed     |
   |-------+-----------------+-----------------+----------------|
   | 256KB |   pins 1 & 2    |   pins 1 & 2    |   pins 1 & 2   |
   |       |     closed      |     closed      |     closed     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   CPU TYPE CONFIGURATION                   |
   |------------------------------------------------------------|
   |  Type   |       W5       |       W6       |       W7       |
   |---------+----------------+----------------+----------------|
   | 80486SX |   pins 2 & 3   |   pins 2 & 3   |      Open      |
   |         |     closed     |     closed     |                |
   |---------+----------------+----------------+----------------|
   | 80487SX |   pins 1 & 2   |   pins 1 & 2   |   pins 1 & 2   |
   |         |     closed     |     closed     |     closed     |
   |---------+----------------+----------------+----------------|
   | 80486DX |   pins 1 & 2   |   pins 1 & 2   |   pins 2 & 3   |
   |         |     closed     |     closed     |     closed     |
   +------------------------------------------------------------+