J-MARK COMPUTER CORPORATION
486SX/DX VERSION II
|
Processor |
80486SX/80487SX/80486DX/80486DX2 |
|
Processor Speed |
16/20/25/33/50(internal)/50/66(internal) MHz |
|
Chip Set |
OPTI |
|
Max. onboard DRAM |
32MB |
|
Cache |
64/128/256KB |
|
BIOS |
AMI |
|
Dimensions |
240mm x 220mm |
|
I/O Options |
None |
|
NPU Options |
None |
|
CONNECTIONS | |||
|
Purpose |
Location |
Purpose |
Location |
|
External battery |
J1 |
Speaker |
J17 |
|
Turbo switch |
JP9 |
Power LED & keylock |
J18 |
|
Turbo LED |
JP10 |
Reset switch |
SW1 |
|
USER CONFIGURABLE SETTINGS | |||
|
Function |
Jumper |
Position | |
|
CMOS memory normal operation |
JP1 |
pins 1 & 2 closed | |
|
CMOS memory clear |
JP1 |
pins 2 & 3 closed | |
|
Monitor type select color |
JP2 |
Closed | |
|
Monitor type select monochrome |
JP2 |
Open | |
|
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 |
|
5MB |
(4) 256K x 9 |
(4) 1M x 9 |
|
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 (U39) |
TAG (U40) |
|
64KB |
(4) 8K x 8 |
NONE |
(1) 8K x 8 |
NONE |
|
128KB |
(4) 32K x 8 |
NONE |
(1) 8K x 8 |
NONE |
|
256KB |
(4) 32K x 8 |
(4) 32K x 8 |
(1) 8K x 8 |
(1) 8K x 8 |
|
256KB |
(4) 32K x 8 |
(4) 32K x 8 |
(1) 32K x 8 |
NONE |
|
CACHE JUMPER CONFIGURATION | ||||||
|
Size |
JP5 |
JP6 |
JP7 |
JP8 |
JP15 |
JP16 |
|
64KB |
Open |
Open |
Open |
pins 2 & 3 |
Open |
Open |
|
128KB |
Closed |
Open |
Closed |
pins 1 & 2 |
Open |
Closed |
|
256KB |
Closed |
Closed |
Closed |
pins 2 & 3 |
closed |
closed |
|
Note:Pins designated should be in the closed postion. | ||||||
|
CPU TYPE CONFIGURATION | ||||
|
CPU type |
JP17 |
JP18 |
JP19 |
JP20 |
|
80486SX PQFP |
Open |
Open |
Closed |
pins 2 & 3 closed |
|
80486SX PGA |
Closed |
Open |
Closed |
pins 2 & 3 closed |
|
80487SX |
Closed |
pins 2 & 3 closed |
Closed |
pins 1 & 2 closed |
|
80486DX/DX2 |
Closed |
pins 1 & 2 closed |
Closed |
pins 1 & 2 closed |
|
CPU SPEED CONFIGURATION | ||||
|
Speed |
JP11 |
JP12 |
JP13 |
JP14 |
|
16MHz |
Closed |
Closed |
Closed |
Closed |
|
20MHz |
Open |
Closed |
Closed |
Open |
|
25MHz |
Open |
Closed |
Open |
Closed |
|
33MHz |
Open |
Open |
Closed |
Open |
|
50i MHz |
Open |
Closed |
Open |
Closed |
|
50MHz |
Open |
Open |
Closed |
Open |
|
66i MHz |
Open |
Open |
Closed |
Open |