(TXT) View Source
       
       # 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                                     
       
 (IMG) IMG 1
          
       
          +------------------------------------------------------------+
          |                        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     |
          +------------------------------------------------------------+