| DIAGRAM | JUMPERS | MEMORY | BIOS |
PC Chips M912 ver:1.7 w/black ISA slots, AMDDX4 support and Real Cache - aka DX-6900 MEMORY SETTINGS
The Cache Memory
Some Cache Memory Considerations
Cache Memory Configurations
Cache Memory Jumper Configurations
The Main Memory
Some Main Memory Considerations
Possible Main Memory Configurations
THE CACHE MEMORY                                                                               TOP
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This system board can support an optional 64KB, 128KB, 256KB, 512KB or 1MB external write back, direct-mapped cache.


SOME CACHE MEMORY CONSIDERATIONS                                  TOP
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Since single bank cache installations (B, D, F) prevent the cache sub-system from using interleaving access, the "Auto Configuration" in the Advanced Chipset Setup must be disabled and the "Cache Read Wait State" must also be set to "3-2-2-2" to ensure proper operation.


CACHE MEMORY CONFIGURATIONS                                                 TOP
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Type   Total Cache        Bank 0         Bank 1       TAG Ram    Pieces
                                  (U21-24)       (U28-31)         (U20)
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  A           64K               8K x 8         8K x 8          8K X 8           9
  B          128K             32K x 8                            8K X 8           5
  C          256K             32K x 8        32K x 8        32K X 8          9
  D          256K             64K x 8                           32K X 8          5
  E          512K             64K x 8        64K x 8        32K X 8          9
  F          512K            128K x 8                           32K X 8         5
  G        1024K            128K x 8      128K X 8        64K X 8         9
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CACHE MEMORY JUMPER CONFIGURATIONS                             TOP
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Type   Cache    JP5    JP10      JP11      JP12       JP13       JP14
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  A        64K     2 - 3     2 - 3     OPEN    OPEN     OPEN     OPEN
  B       128K    1 - 2     1 - 2     OPEN    OPEN     OPEN     SHORT
  C       256K    2 - 3     2 - 3     OPEN    OPEN     SHORT   SHORT
  D       256K    1 - 2     1 - 2     OPEN    OPEN     SHORT   SHORT
                       3 - 4
  E       512K    2 - 3     2 - 3     OPEN    SHORT   SHORT   SHORT
                       4 - 5
  F       512K    1 - 2     1 - 2     OPEN    SHORT   SHORT   SHORT
                       3 - 4
                       5 - 6
  G      1024K   2 - 3    2 - 3    SHORT   SHORT   SHORT   SHORT
                       4 - 5
                       6 - 7
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THE MAIN MEMORY                                                                                   TOP
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There are 2 banks of 72 pins SIMM socket and 1 bank of 30 pins SIMM socket on this board, each bank of 72 pins SIMM consists of only one SIMM socket as denoted as Bank 1, Bank 2; Bank 0 is the socket for the 30 pins' SIMMs. These three banks are not required to be filled in sequence as in Bank 0 first and Bank 3 last. The system board has auto-detection circuitry to sense which bank or banks are filled.


SOME MAIN MEMORY CONSIDERATIONS                                      TOP
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•Maximum memory on-board can not exceed 64MB in any
 combination.
•Bank 0 has to be filled fully (4 pcs.) with same type of SIMMs if
 Bank 0 is to be used at all.
•If Bank 0 is populated, then Bank1 and Bank2 CANNOT house any
 double-sided SIMM modules.
 

POSSIBLE MAIN MEMORY CONFIGURATIONS                              TOP
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        |------BANK 0------| |-------BANK 1-------| |-------BANK 2--------|
#            30 PIN X 4          72 PIN (U17)         72 PIN (U18)
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1          256KB-16MB        256KB-16MB             NONE  
2          256KB-16MB            NONE              256KB-16MB
3          256KB-16MB        256KB-16MB        256KB-16MB
4               NONE                 NONE              256KB-16MB
5               NONE             256KB-16MB             NONE   
6               NONE             256KB-16MB        256KB-16MB


| DIAGRAM | JUMPERS | MEMORY | BIOS |