UNIDENTIFIED
MS-4125 VERSION 2.1
Processor | 80486SX/80487SX/80486DX/ODP486SX/80486DX2/Pentium Overdrive |
Processor Speed | 25/33/40/50(internal)/50/66(internal)MHz |
Chip Set | Contaq |
Max. Onboard DRAM | 32MB |
Cache | 64/128/256KB |
BIOS | AMI |
Dimensions | 254mm x 220mm |
I/O Options | 32-bit VESA local bus slots (2) |
NPU Options | None |

CONNECTIONS | |||
Purpose | Location | Purpose | Location |
Auxiliary keyboard connector | J2 | Turbo LED | J5 pins 12 - 13 |
External battery | J4 | Turbo switch | J5 pins 15 - 17 |
Power LED & keylock | J5 pins 1 - 5 | Reset switch | J5 pins 19 - 20 |
Speaker | J5 pins 6 - 10 | 32-bit VESA local bus slots | SL1 & SL2 |
USER CONFIGURABLE SETTINGS | |||
Function | Jumper | Position | |
» | Battery type select internal | J4 | pins 2 & 3 closed |
Battery type select external | J4 | Closed | |
» | Monitor type select monochrome | JP17 | Open |
Monitor type select color | JP17 | Closed | |
» | Factory configured - do not alter | JP23 | pins 1 & 2 closed |
» | Factory configured - do not alter | JP26 | pins 1 & 2 closed |
» | Factory configured - do not alter | JP37 | 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 |
5MB | (4) 1M x 9 | (4) 256K x 9 |
8MB | (4) 1M x 9 | (4) 1M x 9 |
16MB | (4) 4M x 9 | NONE |
17MB | (4) 4M x 9 | (4) 256K x 9 |
17MB | (4) 256K x 9 | (4) 4M x 9 |
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 | JP1 | JP6 | JP7 |
64KB | pins 1 & 2 closed | pins 2 & 3 closed | pins 2 & 3 closed |
128KB | pins 2 & 3 closed | pins 1 & 2 closed | pins 2 & 3 closed |
256KB | pins 4 & 5 closed | pins 1 & 2 closed | pins 1 & 2 closed |
CPU TYPE CONFIGURATION | |||
Type | JP31 | JP32 | JP33 |
80486SX (PQFP) | Open | Open | pins 1 & 2 closed |
80486SX (PGA) | pins 3 & 4 closed | Open | pins 2 & 3, 4 & 5 closed |
ODP486SX | pins 2 & 3, 4 & 5 closed | pins 1 & 2 closed | pins 2 & 3, 4 & 5 closed |
80487SX | pins 2 & 3, 4 & 5 closed | pins 1 & 2 closed | pins 2 & 3, 4 & 5 closed |
80486DX (PQFP) | pins 1 & 2 closed | pins 4 & 5 closed | pins 1 & 2 closed |
80486DX (PGA) | pins 2 & 3, 4 & 5 closed | pins 2 & 3 closed | pins 2 & 3, 4 & 5 closed |
80486DX2 | pins 2 & 3, 4 & 5 closed | pins 2 & 3 closed | pins 2 & 3, 4 & 5 closed |
Pentium Overdrive | pins 2 & 3, 4 & 5 closed | pins 1 & 2 closed | pins 2 & 3, 4 & 5 closed |
Note: Depending on board revision, it will have either a PGA or PQFP socket. | |||
CPU SPEED CONFIGURATION | ||||
Speed | JP8 | JP12 | JP13 | JP14 |
25MHz | pins 2 & 3 closed | Open | Open | Closed |
33MHz | pins 1 & 2 closed | Closed | Open | Open |
40MHz | pins 1 & 2 closed | Closed | Closed | Open |
50iMHz | pins 2 & 3 closed | Open | Open | Closed |
50MHz | pins 1 & 2 closed | Open | Closed | Open |
66iMHz | pins 1 & 2 closed | Closed | Open | Open |
VESA WAIT STATE CONFIGURATION | |
Wait states | JP19 |
0 wait states | Open |
1 wait state | Closed |
BUS SPEED CONFIGURATION | |
CPU speed | JP20 |
<= 33MHz | Open |
> 33MHz | Closed |
VESA CARD TYPE CONFIGURATION | ||
Card type | JP18 | JP22 |
Normal | Closed | pins 1 & 2 closed |
Weitek P9000 | Open | pins 2 & 3 closed |