J-MARK COMPUTER CORPORATION
J-646B
Processor | Pentium |
Processor Speed | 75/90/100/120/133/150/166MHz |
Chip Set | SIS |
Video Chip Set | None |
Maximum Onboard Memory | 128MB (EDO supported) |
Maximum Video Memory | None |
Cache | 256/512/1024KB |
BIOS | Award |
Dimensions | 330mm x 218mm |
I/O Options | 32-bit PCI slots (3), floppy drive interface, IDE interfaces (2), parallel port, PS/2 mouse interface, serial ports (2) |
NPU Options | None |
CONNECTIONS | |||
Purpose | Location | Purpose | Location |
Speaker | CN1 | Serial port 2 | J8 |
Reset switch | CN2 | Serial port 1 | J9 |
Turbo LED | CN3 | Parallel port | J10 |
Power LED & keylock | CN4 | Floppy drive interface | J11 |
Turbo switch | CN5 | IDE interface 1 | J12 |
IDE interface LED | CN6 | IDE interface 2 | J13 |
BK LED | CN7 | External battery | J15 |
PS/2 mouse interface | J2 | 32-bit PCI slots | PC1 – PC3 |
VGA feature connector | J7 |
USER CONFIGURABLE SETTINGS | |||
Function | Label | Position | |
» | Factory configured - do not alter | J6 | Unidentified |
» | Factory configured - do not alter | JP4 | Unidentified |
» | Factory configured - do not alter | JP5 | Unidentified |
» | Factory configured - do not alter | JP6 | Unidentified |
» | Factory configured - do not alter | JP7 | Unidentified |
» | Factory configured - do not alter | JP9 | Open |
» | Factory configured - do not alter | JP15 | Unidentified |
» | CPU write select write back | JP16 | Pins 1 & 2 closed |
CPU write select write through | JP16 | Pins 2 & 3 closed | |
» | CPU pipeline enabled | JP17 | Pins 2 & 3 closed |
CPU pipeline disabled | JP17 | Pins 1 & 2 closed | |
» | Suspend mode disabled | JP20 | Open |
Suspend mode enabled | JP20 | Closed | |
» | Break switch for suspend mode | JP24 | Pins 2 & 3 closed |
8042 RC enabled | JP24 | Pins 1 & 2 closed | |
» | Monitor type select monochrome | JP25 | Open |
Monitor type select color | JP25 | Closed | |
» | Factory configured - do not alter | JP26 | Unidentified |
» | Factory configured - do not alter | JP27 | Unidentified |
» | Factory configured - do not alter | JP28 | Unidentified |
» | Factory configured - do not alter | JP29 | Unidentified |
» | Factory configured - do not alter | JP30 | Unidentified |
» | Factory configured - do not alter | JP31 | Unidentified |
» | Factory configured - do not alter | JP32 | Unidentified |
» | Factory configured - do not alter | JP33 | Unidentified |
» | Factory configured - do not alter | JP34 | Unidentified |
» | Factory configured - do not alter | JP35 | Unidentified |
» | Factory configured - do not alter | JP36 | Unidentified |
» | Factory configured - do not alter | JP37 | Unidentified |
USER CONFIGURABLE SETTINGS (CON’T) | |||
Function | Label | Position | |
» | CMOS memory normal operation | JP38 | Pins 1 & 2 closed |
CMOS memory clear | JP38 | Pins 2 & 3 closed | |
» | PCICLK speed select 1/2 CPU CLK | JP39 | Closed |
PCICLK speed select = 32MHz | JP39 | Open | |
» | PS/2 IRQ12 enabled | JP41 | Closed |
PS/2 IRQ12 disabled | JP41 | Open | |
» | Factory configured - do not alter | JP42 | Unidentified |
DRAM CONFIGURATION | ||||
Size | Bank 0 | Bank 1 | Bank 2 | Bank 3 |
4MB | (1) 1M x 36 | None | None | None |
8MB | (1) 2M x 36 | None | None | None |
8MB | (1) 1M x 36 | (1) 1M x 36 | None | None |
16MB | (1) 4M x 36 | None | None | None |
16MB | (1) 2M x 36 | (1) 2M x 36 | None | None |
16MB | (1) 1M x 36 | (1) 1M x 36 | (1) 1M x 36 | (1) 1M x 36 |
24MB | (1) 1M x 36 | (1) 1M x 36 | (1) 2M x 36 | (1) 2M x 36 |
32MB | (1) 8M x 36 | None | None | None |
32MB | (1) 4M x 36 | (1) 4M x 36 | None | None |
32MB | (1) 2M x 36 | (1) 2M x 36 | (1) 2M x 36 | (1) 2M x 36 |
40MB | (1) 4M x 36 | (1) 4M x 36 | (1) 1M x 36 | (1) 1M x 36 |
48MB | (1) 4M x 36 | (1) 4M x 36 | (1) 2M x 36 | (1) 2M x 36 |
64MB | (1) 4M x 36 | (1) 4M x 36 | (1) 4M x 36 | (1) 4M x 36 |
72MB | (1) 8M x 36 | (1) 8M x 36 | (1) 1M x 36 | (1) 1M x 36 |
80MB | (1) 8M x 36 | (1) 8M x 36 | (1) 2M x 36 | (1) 2M x 36 |
96MB | (1) 8M x 36 | (1) 8M x 36 | (1) 4M x 36 | (1) 4M x 36 |
128MB | (1) 8M x 36 | (1) 8M x 36 | (1) 8M x 36 | (1) 8M x 36 |
Note: Board accepts EDO memory. Board also accepts x 32 SIMMs. |
DRAM VOLTAGE CONFIGURATION | ||
Voltage | JP1 | |
» | Mixed mode | Pins 3 & 5, 4 & 6 closed |
3.3v | Pins 1 & 3, 2 & 4 closed |
CACHE CONFIGURATION | |||
Size | Bank 0 | Bank 1 | TAG |
256KB (A) | None | (8) 32K x 8 | (1) 8K x 8 |
256KB (B) | (2) 32K x 32 | None | Unidentified |
512KB (A) | None | (8) 64K x 8 | (1) 16K x 8 (Windbond) |
512KB (B) | None | (8) 64K x 8 | (1) 16K/32K x 8 (Aster) |
1MB | None | (8) 128K x 8 | (1) 32K x 8 |
Note: The location of bank 1 & TAG are unidentified. |
CACHE JUMPER CONFIGURATION | |||
Size | JP3 | JP11 | JP42 |
256KB (A) | Pins 1 & 2 closed | Pins 1 & 2 closed | Open |
256KB (B) | Pins 1 & 2 closed | Pins 1 & 2 closed | Open |
512KB (A) | Pins 2 & 3 closed | Open | Closed |
512KB (B) | Pins 2 & 3 closed | Pins 1 & 2 closed | Open |
1MB | Pins 2 & 3 closed | Pins 2 & 3 closed | Open |
CPU SPEED SELECTION | ||||||
CPU speed | Clock speed | Multiplier | JP12 | JP13 | JP18 | JP19 |
75MHz | 50MHz | 1.5x | Closed | Closed | Open | Open |
90MHz | 60MHz | 1.5x | Closed | Open | Open | Open |
100MHz | 66MHz | 1.5x | Open | Closed | Open | Open |
120MHz | 60MHz | 2x | Closed | Open | Open | Closed |
133MHz | 66MHz | 2x | Open | Closed | Open | Closed |
150MHz | 60MHz | 2.5x | Closed | Open | Closed | Closed |
166MHz | 66MHz | 2.5x | Open | Closed | Closed | Closed |
CPU VOLTAGE SELECTION | ||||
Voltage | JP21 | JP22 | JP23 | |
3.3v | Closed | Open | Open | |
» | 3.45v | Open | Closed | Open |
3.6v | Open | Open | Closed |
VGA SELECTION | ||||
Setting | JP2 | JP8 | JP10 | |
» | Onboard VGA | Pins 1 & 2 closed | Closed | Closed |
External VGA card | Pins 2 & 3 closed | Open | Open |