(TXT) View Source
       
       # DELL COMPUTER CORPORATION
       
          Precision 486SX/25, 486DX/33, 486DX2/50
       
          Processor        80486SX/80487SX/80486DX/80486DX2              
          Processor Speed  25/33/50MHz                                   
          Chip Set         OPTI                                          
          Max. Onboard     64MB                                          
          DRAM             
          Cache            64/256KB                                      
          BIOS             AMI                                           
          Dimensions       330mm x 218mm                                 
          I/O Options      Bus mouse port, floppy interface, IDE         
                           interface, parallel port, proprietary         
                           expansion module, serial ports (2), VGA port  
          NPU Options      None                                          
       
 (IMG) IMG 1
          
       
          +------------------------------------------------------------+
          |                        CONNECTIONS                         |
          |------------------------------------------------------------|
          | Purpose             | Location | Purpose        | Location |
          |---------------------+----------+----------------+----------|
          | Internal battery    |   BAT    | Serial port 1  |   J10    |
          | holder              |          |                |          |
          |---------------------+----------+----------------+----------|
          | Proprietary         |   EXP    | IDE interface  |   J23    |
          | expansion module    |          | LED            |          |
          |---------------------+----------+----------------+----------|
          | Bus mouse           |    J1    | Reset switch   |   J24    |
          |---------------------+----------+----------------+----------|
          | IDE interface       |    J5    | Speaker        |   J25    |
          |---------------------+----------+----------------+----------|
          | Floppy drive        |    J6    | Power LED &    |   J26    |
          | interface           |          | keylock        |          |
          |---------------------+----------+----------------+----------|
          | Parallel port       |    J8    | VGA port       |   J27    |
          |---------------------+----------+----------------+----------|
          | Serial port 2       |    J9    |                |          |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 USER CONFIGURABLE SETTINGS                 |
          |------------------------------------------------------------|
          |               Function               | Jumper |  Position  |
          |--------------------------------------+--------+------------|
          | » | Monitor type select color or     |   W1   | pins 1 & 2 |
          |   | monochrome VGA                   |        |   closed   |
          |---+----------------------------------+--------+------------|
          |   | Monitor type select monochrome   |   W1   | pins 2 & 3 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          | » | CMOS memory normal operation     |   W2   | pins 1 & 2 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          |   | CMOS memory clear                |   W2   | pins 2 & 3 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          | » | CPU clock source select SYSCLK/1 |   W3   | pins 1 & 2 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          |   | CPU clock source select SYSCLK/2 |   W3   | pins 2 & 3 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          | » | VGA port enabled                 |  W10   | pins 1 & 2 |
          |   |                                  |        |   closed   |
          |---+----------------------------------+--------+------------|
          |   | VGA port disabled                |  W10   | pins 2 & 3 |
          |   |                                  |        |   closed   |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                     DRAM CONFIGURATION                     |
          |------------------------------------------------------------|
          | Size |   Bank 0    |   Bank 1    |   Bank 2   |   Bank 3   |
          |------+-------------+-------------+------------+------------|
          | 1MB  | (1) 256K x  |    NONE     |    NONE    |    NONE    |
          |      |     36      |             |            |            |
          |------+-------------+-------------+------------+------------|
          | 2MB  | (1) 256K x  | (1) 256K x  |    NONE    |    NONE    |
          |      |     36      |     36      |            |            |
          |------+-------------+-------------+------------+------------|
          | 3MB  | (1) 256K x  | (1) 256K x  | (1) 256K x |    NONE    |
          |      |     36      |     36      |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 4MB  | (1) 256K x  | (1) 256K x  | (1) 256K x | (1) 256K x |
          |      |     36      |     36      |     36     |     36     |
          |------+-------------+-------------+------------+------------|
          | 4MB  | (1) 1M x 36 |    NONE     |    NONE    |    NONE    |
          |------+-------------+-------------+------------+------------|
          | 5MB  | (1) 1M x 36 | (1) 256K x  |    NONE    |    NONE    |
          |      |             |     36      |            |            |
          |------+-------------+-------------+------------+------------|
          | 6MB  | (1) 1M x 36 | (1) 256K x  | (1) 256K x |    NONE    |
          |      |             |     36      |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 8MB  | (1) 1M x 36 | (1) 1M x 36 |    NONE    |    NONE    |
          |------+-------------+-------------+------------+------------|
          | 9MB  | (1) 1M x 36 | (1) 1M x 36 | (1) 256K x |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 10MB | (1) 1M x 36 | (1) 1M x 36 | (1) 256K x | (1) 256K x |
          |      |             |             |     36     |     36     |
          |------+-------------+-------------+------------+------------|
          | 12MB | (1) 1M x 36 | (1) 1M x 36 |  (1) 1M x  |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 16MB | (1) 1M x 36 | (1) 1M x 36 |  (1) 1M x  |  (1) 1M x  |
          |      |             |             |     36     |     36     |
          |------+-------------+-------------+------------+------------|
          | 16MB | (1) 4M x 36 |    NONE     |    NONE    |    NONE    |
          |------+-------------+-------------+------------+------------|
          | 17MB | (1) 4M x 36 | (1) 256K x  |    NONE    |    NONE    |
          |      |             |     36      |            |            |
          |------+-------------+-------------+------------+------------|
          | 18MB | (1) 4M x 36 | (1) 256K x  | (1) 256K x |    NONE    |
          |      |             |     36      |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 20MB | (1) 4M x 36 | (1) 1M x 36 |    NONE    |    NONE    |
          |------+-------------+-------------+------------+------------|
          | 24MB | (1) 4M x 36 | (1) 1M x 36 |  (1) 1M x  |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 32MB | (1) 4M x 36 | (1) 4M x 36 |    NONE    |    NONE    |
          |------+-------------+-------------+------------+------------|
          | 33MB | (1) 4M x 36 | (1) 4M x 36 | (1) 256K x |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 34MB | (1) 4M x 36 | (1) 4M x 36 | (1) 256K x | (1) 256K x |
          |      |             |             |     36     |     36     |
          |------+-------------+-------------+------------+------------|
          | 36MB | (1) 4M x 36 | (1) 4M x 36 |  (1) 1M x  |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 40MB | (1) 4M x 36 | (1) 4M x 36 |  (1) 1M x  |  (1) 1M x  |
          |      |             |             |     36     |     36     |
          |------+-------------+-------------+------------+------------|
          | 48MB | (1) 4M x 36 | (1) 4M x 36 |  (1) 4M x  |    NONE    |
          |      |             |             |     36     |            |
          |------+-------------+-------------+------------+------------|
          | 64MB | (1) 4M x 36 | (1) 4M x 36 |  (1) 4M x  |  (1) 4M x  |
          |      |             |             |     36     |     36     |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                    CACHE CONFIGURATION                     |
          |------------------------------------------------------------|
          |            Size            |            Bank 0             |
          |----------------------------+-------------------------------|
          |            64KB            |          (8) 8K x 8           |
          |----------------------------+-------------------------------|
          |           256KB            |          (8) 32K x 8          |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 CACHE JUMPER CONFIGURATION                 |
          |------------------------------------------------------------|
          | Size  |       W4        |       W5        |       W9       |
          |-------+-----------------+-----------------+----------------|
          | 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   |       W6       |       W7       |       W8       |
          |---------+----------------+----------------+----------------|
          | 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     |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |      VGA REFRESH CONFIGURATION (800 X 600 RESOLUTION)      |
          |------------------------------------------------------------|
          |        Refresh Rate        |     SW1/1     |     SW1/2     |
          |----------------------------+---------------+---------------|
          |          |      56Hz       |      Off      |      Off      |
          |----------+-----------------+---------------+---------------|
          |          |      56Hz       |      On       |      On       |
          |----------+-----------------+---------------+---------------|
          | »        |      60Hz       |      Off      |      On       |
          |----------+-----------------+---------------+---------------|
          |          |      72Hz       |      On       |      Off      |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |     VGA REFRESH CONFIGURATION (1024 X 768 RESOLUTION)      |
          |------------------------------------------------------------|
          |        Refresh Rate         |     SW1/3     |    SW1/4     |
          |-----------------------------+---------------+--------------|
          | »      |     Interlaced     |      Off      |     Off      |
          |--------+--------------------+---------------+--------------|
          |        |        60Hz        |      Off      |      On      |
          |--------+--------------------+---------------+--------------|
          |        |        70Hz        |      On       |     Off      |
          |--------+--------------------+---------------+--------------|
          |        |        72Hz        |      On       |      On      |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |              VGA REFRESH CONFIGURATION               |     |
          |------------------------------------------------------|     |
          |             Refresh Rate              |    SW1/5     |     |
          |---------------------------------------+--------------|     |
          | » |    31.5Hz horizontal, 60/70Hz     |     Off      |     |
          |   |             vertical              |              |     |
          |---+-----------------------------------+--------------|     |
          |   | 40Hz horizontal, 75/80Hz vertical |      On      |     |
          |   |            (see note)             |              |     |
          |---+--------------------------------------------------------|
          |   | Note :Use 75Hz for video modes 0 through 10h and 13h.  |
          |   | Use 80Hz for video modes 11h and 12h.                  |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                     VRAM CONFIGURATION                     |
          |------------------------------------------------------------|
          |            Size            |            Bank 0             |
          |----------------------------+-------------------------------|
          | » |         512KB          |             NONE              |
          |---+------------------------+-------------------------------|
          |   |          1MB           |        (4) 44256 ZIPPs        |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 VRAM SWITCH CONFIGURATION                  |
          |------------------------------------------------------------|
          |               Size               |          SW1/6          |
          |----------------------------------+-------------------------|
          | »    |           512KB           |           On            |
          |------+---------------------------+-------------------------|
          |      |            1MB            |           Off           |
          +------------------------------------------------------------+