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       # J-BOND COMPUTER SYSTEMS CORPORATION
       
          486 VL450C-1
       
          Processor  80486SX/80486DX/80486DX2                              
          Processor  20/25/33/40(internal)/50(internal)/50/66(internal)MHz 
          Speed      
          Chip Set   SIS                                                   
          Max.       32MB                                                  
          Onboard    
          DRAM       
          Cache      64/128/256KB                                          
          BIOS       AMI                                                   
          Dimensions 230mm x 218mm                                         
          I/O        32-bit VESA local bus slots (2)                       
          Options    
          NPU        None                                                  
          Options    
       
 (IMG) IMG 1
          
       
          +------------------------------------------------------------+
          |                        CONNECTIONS                         |
          |------------------------------------------------------------|
          | Purpose           | Location | Purpose          | Location |
          |-------------------+----------+------------------+----------|
          | External battery  |    J1    | Turbo LED        |    J5    |
          |-------------------+----------+------------------+----------|
          | Power LED &       |    J2    | Reset switch     |    J6    |
          | keylock           |          |                  |          |
          |-------------------+----------+------------------+----------|
          | Speaker           |    J3    | 32-bit VESA      |  SL1 &   |
          |                   |          | Local bus slots  |   SL2    |
          |-------------------+----------+------------------+----------|
          | Turbo switch      |    J4    |                  |          |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 USER CONFIGURABLE SETTINGS                 |
          |------------------------------------------------------------|
          |              Function               | Jumper  |  Position  |
          |-------------------------------------+---------+------------|
          | » | Factory configured - do not     |   J7    |    Open    |
          |   | alter                           |         |            |
          |---+---------------------------------+---------+------------|
          | » | A20 type select fast gate       |   JP2   | pins 1 & 2 |
          |   |                                 |         |   closed   |
          |---+---------------------------------+---------+------------|
          |   | A20 type select keyboard        |   JP2   | pins 2 & 3 |
          |   | controller gate                 |         |   closed   |
          |---+---------------------------------+---------+------------|
          | » | CMOS memory normal operation    |   JP3   |    Open    |
          |---+---------------------------------+---------+------------|
          |   | CMOS memory clear               |   JP3   | pins 2 & 3 |
          |   |                                 |         |   closed   |
          |---+---------------------------------+---------+------------|
          | » | VESA local bus normal operation |  JP27   | pins 1 & 2 |
          |   |                                 |         |   closed   |
          |---+---------------------------------+---------+------------|
          |   | VESA local bus compatibility    |  JP27   | pins 2 & 3 |
          |   | problems (See note below)       |         |   closed   |
          |---+---------------------------------+---------+------------|
          | » | PQFP CPU enabled                |  JSX6   |    Open    |
          |---+---------------------------------+---------+------------|
          |   | PQFP CPU disabled               |  JSX6   |   Closed   |
          |------------------------------------------------------------|
          | Note: If compatibility problems arise with nonstandard     |
          | VESA local bus peripherals, jumper pins 2 & 3.             |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                     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        |
          |------------------+--------------------+--------------------|
          |       8MB        |     (4) 1M x 9     |     (4) 1M x 9     |
          |------------------+--------------------+--------------------|
          |       16MB       |     (4) 4M x 9     |        NONE        |
          |------------------+--------------------+--------------------|
          |       20MB       |     (4) 1M x 9     |     (4) 4M x 9     |
          |------------------+--------------------+--------------------|
          |       32MB       |     (4) 4M x 9     |     (4) 4M x 9     |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                    CACHE CONFIGURATION                     |
          |------------------------------------------------------------|
          | Size  |   Bank 0    |   Bank 1    |          TAG           |
          |-------+-------------+-------------+------------------------|
          | 64KB  | (4) 8K x 8  | (4) 8K x 8  | (1) 8K x 8 or (1) 32K  |
          |       |             |             |          x 8           |
          |-------+-------------+-------------+------------------------|
          | 128KB | (4) 32K x 8 |    NONE     | (1) 8K x 8 or (1) 32K  |
          |       |             |             |          x 8           |
          |-------+-------------+-------------+------------------------|
          | 256KB | (4) 32K x 8 | (4) 32K x 8 |      (1) 32K x 8       |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 CACHE JUMPER CONFIGURATION                 |
          |------------------------------------------------------------|
          |  Size   |   JP4    |        JP5        |   JP6   |   JP7   |
          |---------+----------+-------------------+---------+---------|
          |  64KB   |   Open   |       Open        |  Open   |  Open   |
          |---------+----------+-------------------+---------+---------|
          |  128KB  |  Closed  | pins 1 & 2 closed |  Open   | Closed  |
          |---------+----------+-------------------+---------+---------|
          |  256KB  |  Closed  | pins 2 & 3 closed | Closed  | Closed  |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                   CPU TYPE CONFIGURATION                   |
          |------------------------------------------------------------|
          |    Type     |  JSX1   |  JSX2   |  JSX3  |  JSX4  |  JSX5  |
          |-------------+---------+---------+--------+--------+--------|
          |   80486SX   |  Open   |  Open   |  Open  | Closed |  Open  |
          |-------------+---------+---------+--------+--------+--------|
          |   80487SX   |  Open   | Closed  | Closed |  Open  | Closed |
          |-------------+---------+---------+--------+--------+--------|
          | 80486DX/DX2 | Closed  |  Open   | Closed |  Open  | Closed |
          |-------------+---------+---------+--------+--------+--------|
          |  Overdrive  |  Open   | Closed  | Closed |  Open  | Closed |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  CPU SPEED CONFIGURATION                   |
          |------------------------------------------------------------|
          |     Speed     |     JP20     |     JP21     |     JP22     |
          |---------------+--------------+--------------+--------------|
          |     20MHz     |     Open     |     Open     |     Open     |
          |---------------+--------------+--------------+--------------|
          |     25MHz     |    Closed    |     Open     |     Open     |
          |---------------+--------------+--------------+--------------|
          |     33MHz     |    Closed    |    Closed    |    Closed    |
          |---------------+--------------+--------------+--------------|
          |     40MHz     |    Closed    |    Closed    |     Open     |
          |---------------+--------------+--------------+--------------|
          |    50iMHz     |    Closed    |     Open     |     Open     |
          |---------------+--------------+--------------+--------------|
          |     50MHz     |     Open     |     Open     |    Closed    |
          |---------------+--------------+--------------+--------------|
          |    66iMHz     |    Closed    |    Closed    |    Closed    |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |          VESA WAIT STATE/BUS SPEED CONFIGURATION           |
          |------------------------------------------------------------|
          | CPU speed |  Wait states  |  JP8   |  JP9  | JP10  | JP11  |
          |-----------+---------------+--------+-------+-------+-------|
          |  < 33MHz  | 0 wait states |  Open  | Open  | Open  | Open  |
          |-----------+---------------+--------+-------+-------+-------|
          |  > 33MHz  | 1 wait state  | Short  | Short | Short | Short |
          +------------------------------------------------------------+