CHAINTECH COMPUTER COMPANY, LTD.
VESA MAINBOARD SIS 486 (REV. 2)
Processor |
80486SX/CX486M7/80486DX/80486DX2/Pentium Overdrive |
Processor Speed |
25/33/40/50(internal)/50/66(internal)MHz |
Chip Set |
SIS |
Max. Onboard DRAM |
128MB |
Cache |
128/256/512KB |
BIOS |
AMI/Award |
Dimensions |
330mm x 218mm |
I/O Options |
32-bit VESA local bus slots (3), green PC connector |
NPU Options |
None |
CONNECTIONS | |||
Purpose |
Location |
Purpose |
Location |
External battery |
J1 |
Reset switch |
J6 |
Turbo switch |
J3 |
Power LED & keylock |
J7 |
Turbo LED |
J4 |
Green PC connector |
JP26 |
Speaker |
J5 |
32-bit VESA local bus slots |
SL1 - SL3 |
USER CONFIGURABLE SETTINGS | |||
Function |
Jumper |
Position | |
» |
SMOUT type select normal mode |
J2 |
Closed |
SMOUT type select standby mode |
J2 |
Open | |
» |
CMOS memory normal operation |
JP16 |
pins 1 & 2 closed |
CMOS memory clear |
JP16 |
pins 2 & 3 closed | |
» |
Factory configured - do not alter |
JP18 |
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 |
17MB |
(4) 256K x 9 |
(4) 4M x 9 |
20MB |
(4) 1M x 9 |
(4) 4M x 9 |
32MB |
(4) 4M x 9 |
(4) 4M x 9 |
64MB |
(4) 16M x 9 |
NONE |
65MB |
(4) 256K x 9 |
(4) 16M x 9 |
68MB |
(4) 1M x 9 |
(4) 16M x 9 |
80MB |
(4) 4M x 9 |
(4) 16M x 9 |
128MB |
(4) 16M x 9 |
(4) 16M x 9 |
CACHE CONFIGURATION | |||
Size |
Bank 0 |
Bank 1 |
TAG |
128KB |
(4) 32K x 8 |
NONE |
(1) 8K x 8 |
256KB |
(4) 32K x 8 |
(4) 32K x 8 |
(1) 32K x 8 |
512KB |
(4) 128K x 8 |
NONE |
(1) 32K x 8 |
CACHE JUMPER CONFIGURATION | ||||
Size |
JP1 |
JP2 |
JP3 |
JP4 |
128KB |
pins 1 & 2 closed |
pins 1 & 2 closed |
pins 1 & 2, 3 & 4 closed |
pins 1 & 2 closed |
256KB |
pins 2 & 3 closed |
pins 2 & 3 closed |
pins 2 & 3, 4 & 5 closed |
pins 1 & 2 closed |
512KB |
pins 1 & 2 closed |
pins 2 & 3 closed |
pins 1 & 2, 3 & 4 closed |
pins 2 & 3 closed |
CPU TYPE CONFIGURATION | |||||||
Type |
JP8 |
JP9 |
JP10 |
JP11 |
JP12 |
JP13 |
JP14 |
80486SX |
2 & 3 |
Open |
2 & 3 |
Open |
3 & 4 |
1 & 2 |
2 & 3 |
CX486M7 |
1 & 2 |
Closed |
2 & 3 |
2 & 3 |
2 & 3 |
Open |
1 & 2 |
80486DX/DX2 |
1 & 2 |
Closed |
2 & 3 |
2 & 3 |
3 & 4 |
1 & 2 |
2 & 3 |
P23S |
2 & 3 |
Open |
2 & 3 |
Open |
3 & 4 |
1 & 2 |
2 & 3 |
P24D |
1 & 2 |
Closed |
1 & 2 |
2 & 3 |
1 & 2 |
2 & 3 |
2 & 3 |
P24S |
1 & 2 |
Closed |
2 & 3 |
2 & 3 |
3 & 4 |
1 & 2 |
2 & 3 |
P24T |
1 & 2 |
Closed |
1 & 2 |
1 & 2 |
3 & 4 |
Open |
1 & 2 |
Note: Pins designated should be in the closed position. |
CPU TYPE CONFIGURATION (CON’T) | ||||||
Type |
JP15 |
JP21 |
JP22 |
JP24 |
JP25 |
JP30 |
80486SX |
4 & 5 |
2 & 3 |
1 & 2 |
Open |
Open |
Open |
CX486M7 |
2 & 3 |
1 & 2 |
2 & 3 |
2 & 3 |
2 & 3 |
Open |
80486DX/DX2 |
4 & 5 |
2 & 3 |
1 & 2 |
Open |
Open |
Open |
P23S |
4 & 5 |
2 & 3 |
1 & 2 |
Open |
Open |
Open |
P24D |
4 & 5 |
2 & 3 |
1 & 2 |
Open |
1 & 2 |
Closed |
P24S |
4 & 5 |
2 & 3 |
1 & 2 |
Open |
Open |
Open |
P24T |
1 & 2 |
1 & 2 |
1 & 2 |
1 & 2 |
1 & 2 |
Open |
Note: Pins designated should be in the closed position. |
CPU SPEED CONFIGURATION | |||
Speed |
JP5 |
JP6 |
JP7 |
25MHz |
Open |
Closed |
Open |
33MHz |
Closed |
Closed |
Closed |
40MHz |
Open |
Closed |
Closed |
50iMHz |
Open |
Closed |
Open |
50MHz |
Closed |
Open |
Open |
66iMHz |
Closed |
Closed |
Closed |
CPU CLOCK DELAY CONFIGURATION | |
Delay |
JP20 |
0 delay |
pins 1 & 2 closed |
1 gate buffer delay |
pins 2 & 3 closed |
CPU INPUT FREQUENCY CONFIGURATION | |
input |
JP23 |
Single input |
pins 1 & 2 closed |
Double input |
pins 2 & 3 closed |
VESA WAIT STATE CONFIGURATION | |
Wait states |
JP28 |
0 wait states |
pins 1 & 2 closed |
1 wait state |
pins 2 & 3 closed |
BUS SPEED CONFIGURATION | |
CPU speed |
JP29 |
<= 33MHz |
pins 1 & 2 closed |
> 33MHz |
pins 2 & 3 closed |