TEXT View Source
# J-MARK COMPUTER CORPORATION
J-756A
Device Type Mainboard
Processor Pentium Pro
Processor Speed 150/180/200MHz
Chip Set Intel 440FX
Maximum Onboard 512MB (EDO supported)
Memory
Cache 256/512KB (located on Pentium Pro CPU)
BIOS Unidentified
Dimensions 330mm x 218mm
I/O Options 32-bit PCI slots (4), floppy drive interface,
green PC connector, IDE interfaces (2),
parallel port, PS/2 mouse interface, serial
ports (2), IR connector, USB connectors (2)
IMG IMG 1
+------------------------------------------------------------+
| CONNECTIONS |
|------------------------------------------------------------|
| Purpose | Location | Purpose | Location |
|-------------------+----------+------------------+----------|
| IDE interface LED | C1 | Serial port 1 | J7 |
|-------------------+----------+------------------+----------|
| Turbo LED | C2 | Floppy drive | J8 |
| | | interface | |
|-------------------+----------+------------------+----------|
| Reset switch | C3 | IDE interface 2 | J9 |
|-------------------+----------+------------------+----------|
| Speaker | C4 | CPU fan power | J11 |
|-------------------+----------+------------------+----------|
| Green PC | C5 | External battery | J19 |
| connector | | | |
|-------------------+----------+------------------+----------|
| Turbo switch | C6 | IR connector | JP1 |
|-------------------+----------+------------------+----------|
| Power LED & | C7 | USB connector 1 | JP2 |
| keylock | | | |
|-------------------+----------+------------------+----------|
| Serial port 2 | J4 | USB connector 2 | JP3 |
|-------------------+----------+------------------+----------|
| Parallel port | J5 | 32-bit PCI slots | PC1 – |
| | | | PC4 |
|-------------------+----------+------------------+----------|
| IDE interface 1 | J6 | | |
+------------------------------------------------------------+
+------------------------------------------------------------+
| USER CONFIGURABLE SETTINGS |
|------------------------------------------------------------|
| Function | Label | Position |
|-----------------------------------+-------+----------------|
| » | CMOS memory normal operation | J19 | Pins 2 & 3 |
| | | | closed |
|---+-------------------------------+-------+----------------|
| | CMOS memory clear | J19 | Pins 3 & 4 |
| | | | closed |
|---+-------------------------------+-------+----------------|
| | Battery type select external | J19 | Open |
|---+-------------------------------+-------+----------------|
| | Flash BIOS voltage select 12v | JP15 | Pins 2 & 3 |
| | | | closed |
|---+-------------------------------+-------+----------------|
| | Flash BIOS voltage select 5v | JP15 | Pins 1 & 2 |
| | | | closed |
|---+-------------------------------+-------+----------------|
| » | CMOS memory normal operation | JP23 | Open |
|---+-------------------------------+-------+----------------|
| | CMOS memory clear | JP23 | Closed |
|---+-------------------------------+-------+----------------|
| | PS/2 mouse IRQ enabled | JP25 | Closed |
|---+-------------------------------+-------+----------------|
| | PS/2 mouse IRQ disabled | JP25 | Open |
+------------------------------------------------------------+
+------------------------------------------------------------+
| SIMM CONFIGURATION |
|------------------------------------------------------------|
| Size | Bank 0 | Bank 1 |
|------------------+--------------------+--------------------|
| 8MB | (2) 1M x 36 | None |
|------------------+--------------------+--------------------|
| 16MB | (2) 2M x 36 | None |
|------------------+--------------------+--------------------|
| 16MB | (2) 1M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 24MB | (2) 2M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 32MB | (2) 4M x 36 | None |
|------------------+--------------------+--------------------|
| 32MB | (2) 2M x 36 | (2) 2M x 36 |
|------------------+--------------------+--------------------|
| 40MB | (2) 4M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 48MB | (2) 4M x 36 | (2) 2M x 36 |
|------------------+--------------------+--------------------|
| 64MB | (2) 8M x 36 | None |
+------------------------------------------------------------+
+------------------------------------------------------------+
| SIMM CONFIGURATION (CON’T) |
|------------------------------------------------------------|
| Size | Bank 0 | Bank 1 |
|------------------+--------------------+--------------------|
| 64MB | (2) 4M x 36 | (2) 4M x 36 |
|------------------+--------------------+--------------------|
| 72MB | (2) 8M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 80MB | (2) 8M x 36 | (2) 2M x 36 |
|------------------+--------------------+--------------------|
| 96MB | (2) 8M x 36 | (2) 4M x 36 |
|------------------+--------------------+--------------------|
| 128MB | (2) 8M x 36 | (2) 8M x 36 |
|------------------+--------------------+--------------------|
| 128MB | (2) 16M x 36 | None |
|------------------+--------------------+--------------------|
| 136MB | (2) 16M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 144MB | (2) 16M x 36 | (2) 2M x 36 |
|------------------+--------------------+--------------------|
| 160MB | (2) 16M x 36 | (2) 4M x 36 |
|------------------+--------------------+--------------------|
| 192MB | (2) 16M x 36 | (2) 8M x 36 |
|------------------+--------------------+--------------------|
| 256MB | (2) 16M x 36 | (2) 16M x 36 |
|------------------+--------------------+--------------------|
| 256MB | (2) 32M x 36 | None |
|------------------+--------------------+--------------------|
| 264MB | (2) 32M x 36 | (2) 1M x 36 |
|------------------+--------------------+--------------------|
| 272MB | (2) 32M x 36 | (2) 2M x 36 |
|------------------+--------------------+--------------------|
| 288MB | (2) 32M x 36 | (2) 4M x 36 |
|------------------+--------------------+--------------------|
| 320MB | (2) 32M x 36 | (2) 8M x 36 |
|------------------+--------------------+--------------------|
| 384MB | (2) 32M x 36 | (2) 16M x 36 |
|------------------+--------------------+--------------------|
| 512MB | (2) 32M x 36 | (2) 32M x 36 |
|------------------------------------------------------------|
| Note: Board accepts EDO memory. |
+------------------------------------------------------------+
+------------------------------------------------------------+
| CACHE CONFIGURATION |
|------------------------------------------------------------|
| Note: 256KB/512KB cache is located on the Pentium Pro CPU. |
+------------------------------------------------------------+
+-----------------------------------------------------------------+
| CPU SPEED SELECTION |
|-----------------------------------------------------------------|
| CPU |Clock|Multiplier| JP17 | JP18 | JP19 | JP20 | JP21 | JP22 |
|speed |speed| | | | | | | |
|------+-----+----------+------+------+------+------+------+------|
|150MHz|60MHz| 2.5x | Open |Closed| Open |Closed|Closed|Closed|
|------+-----+----------+------+------+------+------+------+------|
|180MHz|60MHz| 3x | Open |Closed|Closed| Open |Closed|Closed|
|------+-----+----------+------+------+------+------+------+------|
|200MHz|66MHz| 3x |Closed| Open |Closed| Open |Closed|Closed|
+-----------------------------------------------------------------+
+------------------------------------------------------------+
| CPU VOLTAGE SELECTION |
|------------------------------------------------------------|
| Voltage | JP12/pins 1 | JP12/pins | JP12/pins | JP12/pins |
| | & 2 | 3 & 4 | 5 & 6 | 7 & 8 |
|---------+--------------+-----------+-----------+-----------|
| Auto | Open | Open | Open | Open |
|---------+--------------+-----------+-----------+-----------|
| 2.1v | Open | Open | Open | Closed |
|---------+--------------+-----------+-----------+-----------|
| 2.2v | Open | Open | Closed | Open |
|---------+--------------+-----------+-----------+-----------|
| 2.3v | Open | Open | Closed | Closed |
|---------+--------------+-----------+-----------+-----------|
| 2.4v | Open | Closed | Open | Open |
|---------+--------------+-----------+-----------+-----------|
| 2.5v | Open | Closed | Open | Closed |
|---------+--------------+-----------+-----------+-----------|
| 2.6v | Open | Closed | Closed | Open |
|---------+--------------+-----------+-----------+-----------|
| 2.7v | Open | Closed | Closed | Closed |
|---------+--------------+-----------+-----------+-----------|
| 2.8v | Closed | Open | Open | Open |
|---------+--------------+-----------+-----------+-----------|
| 2.9v | Closed | Open | Open | Closed |
|---------+--------------+-----------+-----------+-----------|
| 3.0v | Closed | Open | Closed | Open |
|---------+--------------+-----------+-----------+-----------|
| 3.1v | Closed | Open | Closed | Closed |
|---------+--------------+-----------+-----------+-----------|
| 3.2v | Closed | Closed | Open | Open |
|---------+--------------+-----------+-----------+-----------|
| 3.3v | Closed | Closed | Open | Closed |
|---------+--------------+-----------+-----------+-----------|
| 3.4v | Closed | Closed | Closed | Open |
|---------+--------------+-----------+-----------+-----------|
| 3.5v | Closed | Closed | Closed | Closed |
+------------------------------------------------------------+