AMERICAN MEGATRENDS, INC.
=========================

   ATLAS PCI PENTIUM ISA

   Processor    Pentium                                           
   Processor    90/100MHz                                         
   Speed        
   Chip Set     American Megatrends                               
   Max. Onboard 128MB                                             
   DRAM         
   Cache        256/512KB                                         
   BIOS         AMI                                               
   Dimensions   330mm x 218mm                                     
   I/O Options  32-bit PCI bus slots (4), floppy drive interface, 
                IDE interface (2), green PC feature, parallel     
                port, PS/2 mouse port, serial ports (2), green PC 
                monitor connector                                 
   NPU Options  None                                              

<gopher://bitreich.org/I/th99/m/A-B/32111-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose          | Location | Purpose           | Location |
   |------------------+----------+-------------------+----------|
   | Green PC power   |    J1    | Power LED &       |   J15    |
   | connector        |          | keylock           |          |
   |------------------+----------+-------------------+----------|
   | Serial port 1    |    J4    | Speaker           |   J17    |
   |------------------+----------+-------------------+----------|
   | Serial port 2    |    J5    | Reset switch      |   J18    |
   |------------------+----------+-------------------+----------|
   | Parallel port    |    J7    | Turbo switch      |   J20    |
   |------------------+----------+-------------------+----------|
   | Floppy drive     |    J8    | Turbo LED         |   J24    |
   | interface        |          |                   |          |
   |------------------+----------+-------------------+----------|
   | IDE interface    |   J10    | Green PC monitor  |   J25    |
   | (secondary)      |          | connector         |          |
   |------------------+----------+-------------------+----------|
   | IDE interface    |   J11    | IDE interface IDE |   J28    |
   | (primary)        |          |                   |          |
   |------------------+----------+-------------------+----------|
   | PS/2 mouse port  |   J13    | 32-bit PCI bus    |  SL1 -   |
   |                  |          | slots             |   SL4    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |               Function               | Jumper |  Position  |
   |--------------------------------------+--------+------------|
   |>> | Cache memory type select write   |  J29   |    Open    |
   |   | back                             |        |            |
   |---+----------------------------------+--------+------------|
   |   | Cache memory type select write   |  J29   |   Closed   |
   |   | through                          |        |            |
   |---+----------------------------------+--------+------------|
   |>> | Parallel port IRQ select IRQ7    |  J37   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Parallel port IRQ select IRQ5    |  J37   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Serial port 2 IRQ select IRQ3    |  J38   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Serial port 2 IRQ select IRQ4    |  J38   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Serial port 1 IRQ select IRQ4    |  J39   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Serial port 1 IRQ select IRQ3    |  J39   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Onboard mouse IRQ12 enabled      |  J40   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Bus mouse IRQ12 enabled          |  J40   | pins 2 & 3 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |  J47   |    Open    |
   |   | alter                            |        |            |
   |---+----------------------------------+--------+------------|
   |>> | CMOS memory normal operation     |  J48   |    Open    |
   |---+----------------------------------+--------+------------|
   |   | CMOS memory clear                |  J48   |   Closed   |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |  J51   |    Open    |
   |   | alter                            |        |            |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DRAM CONFIGURATION                     |
   |------------------------------------------------------------|
   |       Size       |       Bank 0       |       Bank 1       |
   |------------------+--------------------+--------------------|
   |       2MB        |   (2) 256K x 36    |        NONE        |
   |------------------+--------------------+--------------------|
   |       4MB        |   (2) 256K x 36    |   (2) 256K x 36    |
   |------------------+--------------------+--------------------|
   |       4MB        |   (2) 512K x 36    |        NONE        |
   |------------------+--------------------+--------------------|
   |       8MB        |   (2) 512K x 36    |   (2) 512K x 36    |
   |------------------+--------------------+--------------------|
   |       8MB        |    (2) 1M x 36     |        NONE        |
   |------------------+--------------------+--------------------|
   |       16MB       |    (2) 1M x 36     |    (2) 1M x 36     |
   |------------------+--------------------+--------------------|
   |       16MB       |    (2) 2M x 36     |        NONE        |
   |------------------+--------------------+--------------------|
   |       20MB       |   (2) 512K x 36    |    (2) 2M x 36     |
   |------------------+--------------------+--------------------|
   |       32MB       |    (2) 2M x 36     |    (2) 2M x 36     |
   |------------------+--------------------+--------------------|
   |       32MB       |    (2) 4M x 36     |        NONE        |
   |------------------+--------------------+--------------------|
   |       36MB       |   (2) 512K x 36    |    (2) 4M x 36     |
   |------------------+--------------------+--------------------|
   |       40MB       |    (2) 1M x 36     |    (2) 4M x 36     |
   |------------------+--------------------+--------------------|
   |       48MB       |    (2) 2M x 36     |    (2) 4M x 36     |
   |------------------+--------------------+--------------------|
   |       64MB       |    (2) 4M x 36     |    (2) 4M x 36     |
   |------------------+--------------------+--------------------|
   |       64MB       |    (2) 8M x 36     |        NONE        |
   |------------------+--------------------+--------------------|
   |       80MB       |    (2) 2M x 36     |    (2) 8M x 36     |
   |------------------+--------------------+--------------------|
   |      128MB       |    (2) 8M x 36     |    (2) 8M x 36     |
   |------------------+--------------------+--------------------|
   |      128MB       |    (2) 16M x 36    |        NONE        |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    CACHE CONFIGURATION                     |
   |------------------------------------------------------------|
   |            Size            |            Bank 0             |
   |----------------------------+-------------------------------|
   |           256KB            |          (8) 32K x 8          |
   |----------------------------+-------------------------------|
   |           512KB            |          (8) 64K x 8          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 CACHE JUMPER CONFIGURATION                 |
   |------------------------------------------------------------|
   | Size  |       J21       |       J22       |      J23       |
   |-------+-----------------+-----------------+----------------|
   | 256KB |   pins 1 & 2    |   pins 1 & 2    |   pins 1 & 2   |
   |       |     closed      |     closed      |     closed     |
   |-------+-----------------+-----------------+----------------|
   | 512KB |   pins 2 & 3    |   pins 2 & 3    |   pins 2 & 3   |
   |       |     closed      |     closed      |     closed     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |           CPU OUTPUT SIGNAL BUFFER CONFIGURATION           |
   |------------------------------------------------------------|
   | Output signal buffer |       J30        |       J32        |
   |----------------------+------------------+------------------|
   |    Normal system     |       Open       |       Open       |
   |----------------------+------------------+------------------|
   |    Loaded system     |      Closed      |       Open       |
   |----------------------+------------------+------------------|
   | Extra loaded system  |      Closed      |      Closed      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                  CPU SPEED CONFIGURATION                   |
   |------------------------------------------------------------|
   |             Speed             |            JP33            |
   |-------------------------------+----------------------------|
   |       60/66/90i/100iMHz       |           Closed           |
   |-------------------------------+----------------------------|
   |          50/100iMHz           |            Open            |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |       3.3 VOLT POWER SOURCE CONFIGURATION (INTERNAL)       |
   |------------------------------------------------------------|
   |    J3     |               J34               |   P3 & P4    |
   |-----------+---------------------------------+--------------|
   |   Open    | pins 1 & 2, 3 & 4, 5 & 6 closed |     Open     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |       3.3 VOLT POWER SOURCE CONFIGURATION (EXTERNAL)       |
   |------------------------------------------------------------|
   |               J3                |    J34    |   P3 & P4    |
   |---------------------------------+-----------+--------------|
   | pins 1 & 2, 3 & 4, 5 & 6 closed |   Open    |    Closed    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |              PARALLEL PORT DMA CONFIGURATION               |
   |------------------------------------------------------------|
   |   DMA channel    |        J43         |        J44         |
   |------------------+--------------------+--------------------|
   |       None       |        Open        |        Open        |
   |------------------+--------------------+--------------------|
   |       DRQ0       | pins 1 & 2 closed  | pins 1 & 2 closed  |
   |------------------+--------------------+--------------------|
   |       DRQ1       | pins 3 & 4 closed  | pins 3 & 4 closed  |
   |------------------+--------------------+--------------------|
   |       DRQ3       | pins 5 & 6 closed  | pins 5 & 6 closed  |
   +------------------------------------------------------------+