SCI SYSTEMS, INC.
SCI 486SX/DX SYSTEM BOARD
|
Processor |
80486SX/80486DX |
|
Processor Speed |
25/33MHz |
|
Chip Set |
OPTI |
|
Max. Onboard DRAM |
64MB |
|
Cache |
64/256KB |
|
BIOS |
Unidentified |
|
Dimensions |
330mm x 218mm |
|
I/O Options |
Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA port |
|
NPU Options |
None |
|
CONNECTIONS | |||
|
Purpose |
Location |
Purpose |
Location |
|
PS/2 mouse port |
J1 |
IDE interface LED |
J23 |
|
IDE interface |
J5 |
Reset switch |
J24 |
|
Floppy drive interface |
J6 |
Speaker |
J25 |
|
Parallel port |
J8 |
Power LED & keylock |
J26 |
|
Serial port 2 |
J9 |
VGA port |
J27 |
|
Serial port 1 |
J10 | ||
|
USER CONFIGURABLE SETTINGS | |||
|
Function |
Jumper/Switch |
Position | |
|
|
Monitor type select color |
W1 |
pins 1 & 2 closed |
|
Monitor type select monochrome |
W1 |
pins 2 & 3 closed | |
|
|
CMOS memory normal operation |
W2 |
pins 1 & 2 closed |
|
CMOS memory clear |
W2 |
pins 2 & 3 closed | |
|
|
SYSCLK enabled |
W3 |
pins 2 & 3 closed |
|
SYSCLK/2 enabled |
W3 |
pins 1 & 2 closed | |
|
|
On board VGA enabled |
W10 |
pins 1 & 2 closed |
|
On board VGA disabled |
W10 |
pins 2 & 3 closed | |
|
|
Video horizontal scan rate select 31.5 kHz |
SW1/5 |
On |
|
Video horizontal scan rate select 40kHz |
SW1/5 |
Off | |
|
|
Video memory select 512KB |
SW1/6 |
On |
|
Video memory select 1MB |
SW1/6 |
Off | |
|
DRAM CONFIGURATION | ||||
|
Size |
Bank 0 |
Bank 1 |
Bank 2 |
Bank 3 |
|
1MB |
(1) 256K x 36 |
NONE |
NONE |
NONE |
|
2MB |
(1) 256K x 36 |
(1) 256K x 36 |
NONE |
NONE |
|
4MB |
(1) 1M x 36 |
NONE |
NONE |
NONE |
|
5MB |
(1) 256K x 36 |
(1) 1M x 36 |
NONE |
NONE |
|
6MB |
(1) 256K x 36 |
(1) 256K x 36 |
(1) 1M x 36 |
NONE |
|
8MB |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
NONE |
|
9MB |
(1) 256K x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
|
10MB |
(1) 256K x 36 |
(1) 256K x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
12MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
|
13MB |
(1) 256K x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
16MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
16MB |
(1) 4M x 36 |
NONE |
NONE |
NONE |
|
20MB |
(1) 1M x 36 |
(1) 4M x 36 |
NONE |
NONE |
|
20MB |
(1) 4M x 36 |
(1) 1M x 36 |
NONE |
NONE |
|
24MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 4M x 36 |
NONE |
|
24MB |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
NONE |
|
24MB |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
|
28MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
|
28MB |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
28MB |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
32MB |
(1) 4M x 36 |
(1) 4M x 36 |
NONE |
NONE |
|
36MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
|
36MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
NONE |
|
36MB |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
NONE |
|
40MB |
(1) 1M x 36 |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
|
40MB |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
|
40MB |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
|
40MB |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 1M x 36 |
|
DRAM CONFIGURATION (CONT) | ||||
|
Size |
Bank 0 |
Bank 1 |
Bank 2 |
Bank 3 |
|
48MB |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
NONE |
|
52MB |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
|
52MB |
(1) 4M x 36 |
(1) 1M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
|
52MB |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 1M x 36 |
|
64MB |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
(1) 4M x 36 |
|
CACHE CONFIGURATION | |||
|
Size |
Bank 0 |
Bank 1 |
TAG |
|
64KB |
(4) 8K x 8 |
(4) 8K x 8 |
(2) 16K x 4 |
|
256KB |
(4) 32K x 8 |
(4) 32K x 8 |
(2) 16K x 4 |
|
CACHE JUMPER CONFIGURATION | ||||
|
Size |
W4 |
W5 |
W9 |
W11 |
|
64KB |
pins 2 & 3 closed |
pins 2 & 3 closed |
pins 2 & 3 closed |
pins 2 & 3 closed |
|
256KB |
pins 1 & 2 closed |
pins 1 & 2 closed |
pins 1 & 2 closed |
pins 2 & 3 closed |
|
CPU TYPE CONFIGURATION | |||
|
Type |
W6 |
W7 |
W8 |
|
486SX |
pins 2 & 3 closed |
pins 2 & 3 closed |
N/A |
|
487SX |
pins 1 & 2 closed |
pins 1 & 2 closed |
pins 1 & 2 closed |
|
486DX |
pins 1 & 2 closed |
pins 1 & 2 closed |
pins 2 & 3 closed |
|
VIDEO CONFIGURATION (800 X 600) | |||
|
Refresh rate |
SW1/1 |
SW1/2 | |
|
60Hz |
Off |
On | |
|
56Hz |
Off |
Off | |
|
56Hz |
On |
On | |
|
72Hz |
On |
Off | |
|
VIDEO CONFIGURATION (1024 X 768) | |||
|
Refresh rate |
SW1/3 |
SW1/4 | |
|
Interlaced |
Off |
Off | |
|
60Hz |
Off |
On | |
|
70Hz |
On |
Off | |
|
72Hz |
On |
On | |
|
VIDEO MEMORY CONFIGURATION | ||
|
Size |
Bank 0 |
Bank 1 |
|
512KB |
(4) 256K x 4 |
NONE |
|
1MB |
(4) 256K x 4 |
(4) 256K x 4 |
|
Note: Bank 0 is factory installed and is not configurable. | ||