UNIDENTIFIED
486SX/DX/DX2-MAINBOARD
|
Processor |
80486SX/80486DX/80486DX2 |
|
Processor Speed |
20/25/33/50(internal)/50/66(internal)MHz |
|
Chip Set |
UNI |
|
Video Chip Set |
None |
|
Maximum Onboard Memory |
32MB |
|
Maximum Video Memory |
None |
|
Cache |
64/128/256KB |
|
BIOS |
AMI |
|
Dimensions |
260mm x 220mm |
|
I/O Options |
32-bit VESA local bus slots (3) |
|
NPU Options |
None |
|
CONNECTIONS | |||
|
Purpose |
Location |
Purpose |
Location |
|
Turbo switch |
H1 |
Reset switch |
H5 |
|
Turbo LED |
H2 |
External battery |
J1 |
|
Power LED & keylock |
H3 |
32-bit VESA local bus slots |
SL1 - SL3 |
|
Speaker |
H4 | ||
|
USER CONFIGURABLE SETTINGS | |||
|
Function |
Label |
Position | |
|
|
Turbo enabled |
H1 |
Closed |
|
Turbo enabled through keyboard (CTRL, ALT, +) |
H1 |
Open | |
|
Turbo disabled through keyboard (CTRL, ALT, -) |
H1 |
Open | |
|
|
CMOS memory normal operation |
J1 |
Pins 2 & 3 closed |
|
CMOS memory clear |
J1 |
Pins 3 & 4 closed | |
|
Battery type select external |
J1 |
Closed | |
|
|
Monitor type select color |
J3 |
Closed |
|
Monitor type select monochrome |
J3 |
Open | |
|
|
VL-BUS clock normal operation |
JP43 |
Pins 2 & 3 closed |
|
VL-BUS clock adjusted |
JP43 |
Pins 1 & 2 closed | |
|
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 |
|
20MB |
(4) 4M x 9 |
(4) 1M x 9 |
|
32MB |
(4) 4M x 9 |
(4) 4M x 9 |
|
CACHE CONFIGURATION | |||
|
Size |
Bank 0 |
Bank 1 |
TAG |
|
64KB |
(4) 8K x 8 |
(4) 8K x 8 |
(1) 8K x 8 |
|
128KB |
(4) 32K x 8 |
None |
(1) 8K x 8 |
|
256KB |
(4) 32K x 8 |
(4) 32K x 8 |
(1) 32K x 8 |
|
CACHE JUMPER CONFIGURATION | ||||
|
Size |
JP6 |
JP7 |
JP8 |
JP9 |
|
64KB |
Open |
Closed |
Open |
Pins 1 & 2 closed |
|
128KB |
Open |
Closed |
Closed |
Pins 1 & 2, 3 & 4 closed |
|
256KB |
Closed |
Closed |
Closed |
Pins 1 & 2, 4 & 5 closed |
|
CPU SPEED SELECTION | |||
|
Speed |
JP29 |
JP30 |
JP31 |
|
20MHz |
Open |
Closed |
Open |
|
25MHz |
Closed |
Open |
Closed |
|
33MHz |
Closed |
Closed |
Open |
|
50iMHz |
Closed |
Open |
Closed |
|
50MHz |
Open |
Closed |
Open |
|
66iMHz |
Closed |
Closed |
Open |
|
CPU TYPE SELECTION | |
|
Type |
JP4 |
|
80486SX |
Pins 5 & 6 closed |
|
80486DX |
Pins 1 & 2, 4 & 5, 6 & 7 closed |
|
80486DX2 |
Pins 1 & 2, 4 & 5, 6 & 7 closed |
|
VL BUS WAIT STATE SELECTION | ||
|
Setting |
JP20 | |
|
0 |
Open | |
|
1 |
Closed | |
|
VL BUS SPEED SELECTION | ||
|
Speed |
JP19 | |
|
<= 33MHz |
Open | |
|
>33 MHz |
Closed | |