UNIDENTIFIED
A486DX4/SIS III
Processor | AM486SX/80486SX/CX486DX/AM486DX/80486DX/AM486DX2/ 80486DX2/AM486DX4/80486DX4 |
Processor Speed | 20/25/33/40/50(internal)/50/66(internal)/75(internal)/ 100(internal)MHz |
Chip Set | SIS |
Video Chip Set | None |
Maximum Onboard Memory | 64MB |
Maximum Video Memory | None |
Cache | 32/64/128/256/512KB |
BIOS | AMI |
Dimensions | 254mm x 218mm |
I/O Options | 32-bit VESA local bus slots (3) |
NPU Options | None |
CONNECTIONS | |||
Purpose | Location | Purpose | Location |
Power LED & keylock | J1 | Power LED | LED1 |
Speaker | J2 | Turbo switch | S1 |
Turbo LED | J4 | 32-bit VESA local bus slots | SL1 - SL3 |
Reset switch | J5 |
USER CONFIGURABLE SETTINGS | |||
Function | Label | Position | |
» | Factory configured - do not alter | J7 | Unidentified |
» | Factory configured - do not alter | J9 | Closed |
» | Factory configured - do not alter | J11 | Open |
» | Factory configured - do not alter | J12 | Open |
» | Factory configured - do not alter | JP17 | Pins 1 & 2 closed |
RC pin used for break switch | JP20 | Pins 1 & 2 closed | |
RC pin used for RC | JP20 | Pins 2 & 3 closed | |
CPU type select any CPU type | JP27 | Open | |
CPU type select CX486S2 only | JP27 | Closed | |
Monitor type select CGA | JP38 | Closed | |
Monitor type select monochrome/EGA/VGA | JP38 | Open | |
» | CMOS memory normal operation | JP39 | Pins 1 & 2 closed |
CMOS memory clear | JP39 | Pins 2 & 3 closed | |
» | Factory configured - do not alter | JP43 | Pins 2 & 3 closed |
» | Factory configured - do not alter | JP71 | Open |
Flash BIOS not installed | JP73 | Pins 1 & 2 closed | |
Flash BIOS installed | JP73 | Pins 2 & 3 closed | |
» | Factory configured - do not alter | JP74 | Unidentified |
» | Factory configured - do not alter | JP75 | Unidentified |
» | Factory configured - do not alter | JP78 | Pins 1 & 2 closed |
» | Factory configured - do not alter | JP79 | Pins 2 & 3 closed |
Turbo disabled | TBSW | Pins 1 & 2 closed | |
Turbo enabled | TBSW | Pins 2 & 3 closed | |
Turbo enabled through S1 | TBSW | Pins 4 & 5 closed |
DRAM CONFIGURATION 1 | |
Size | Bank 0 |
1MB | (4) 256K x 9 |
4MB | (4) 1M x 9 |
16MB | (4) 4M x 9 |
64MB | (4) 16M x 9 |
DRAM CONFIGURATION 2 | ||
Size | Bank 1 | Bank 2 |
1MB | (1) 256K x 36 | None |
2MB | (1) 512K x 36 | None |
4MB | (1) 1M x 36 | None |
4MB | (1) 512K x 36 | (1) 512K x 36 |
8MB | (1) 2M x 36 | None |
8MB | (1) 1M x 36 | (1) 1M x 36 |
16MB | (1) 4M x 36 | None |
DRAM CONFIGURATION 2 (CON’T) | ||
Size | Bank 1 | Bank 2 |
16MB | (1) 2M x 36 | (1) 2M x 36 |
32MB | (1) 8M x 36 | None |
32MB | (1) 4M x 36 | (1) 4M x 36 |
64MB | (1) 8M x 36 | (1) 8M x 36 |
DRAM JUMPER CONFIGURATION | ||
Configuration | JP45 | JP46 |
1 | Pins 2 & 3 closed | Closed |
2 | Pins 1 & 2 closed | Open |
CACHE CONFIGURATION | |||
Size | Bank 0 | Bank 1 | TAG |
32KB | (4) 8K x 8 | None | (1) 8K x 8 |
64KB | (4) 8K x 8 | (4) 8K x 8 | (1) 8K x 8 |
128KB | (4) 32K x 8 | None | (1) 8K x 8 |
256KB (A) | (4) 32K x 8 | (4) 32K x 8 | (1) 32K x 8 |
256KB (B) | (4) 64K x 8 | None | (1) 32K x 8 |
512KB | (4) 128K x 8 | None | (1) 32K x 8 |
CACHE JUMPER CONFIGURATION | |||||||
Size | JP30 | JP31 | JP32 | JP34 | JP35 | JP36 | JP81 |
32KB | 1 & 2 | 1 & 2 | 1 & 2 | Open | 1 & 2 | 1 & 2 | 2 & 3 |
64KB | 2 & 3 | 1 & 2 | 1 & 2 | 1 & 2 | 2 & 3 | 1 & 2 | 2 & 3 |
128KB | 2 & 3 | 2 & 3 | 1 & 2 | 2 & 3, 4 & 5 | 1 & 2 | 2 & 3 | 2 & 3 |
256KB (A) | 2 & 3 | 2 & 3 | 2 & 3 | 1 & 2, 3 & 4 | 2 & 3 | 2 & 3 | 2 & 3 |
256KB (B) | 2 & 3 | 2 & 3 | 2 & 3 | 2 & 3, 4 & 5 | 1 & 2 | 2 & 3 | 2 & 3 |
512KB | 2 & 3 | 2 & 3 | 2 & 3 | 2 & 3, 4 & 5 | 1 & 2 | 2 & 3 | 1 & 2 |
Note: Pins designated should be in the closed position. |
CPU SPEED SELECTION | |||
Speed | JP5 | JP6 | JP7 |
20MHz | Closed | Open | Closed |
25MHz | Closed | Closed | Open |
33MHz | Open | Closed | Closed |
40MHz | Closed | Open | Open |
50iMHz | Closed | Closed | Open |
50MHz | Open | Open | Closed |
66iMHz | Open | Closed | Closed |
75iMHz | Closed | Closed | Open |
100iMHz | Open | Closed | Closed |
CPU TYPE SELECTION | |||||
Type | J13 | JP8 | JP10 | JP12 | JP13 |
AM486SX | Closed | 2 & 3 | 2 & 3 | Open | Open |
80486SX | Closed | 2 & 3 | 2 & 3 | Open | Open |
CX486DX | Open | 2 & 3 | 2 & 3 | 2 & 3 | 2 & 3 |
AM486DX | Closed | 2 & 3 | 2 & 3 | Open | Open |
80486DX | Closed | 2 & 3 | 2 & 3 | Open | Open |
AM486DX2 | Closed | 2 & 3 | 2 & 3 | Open | Open |
80486DX2 | Closed | 2 & 3 | 2 & 3 | Open | Open |
AM486DX4 | Closed | 2 & 3 | Open | Open | Open |
80486DX4 | Closed | 2 & 3 | Open | Open | Open |
Note: Pins designated should be in the closed position. |
CPU TYPE SELECTION (CON’T) | |||||
Type | JP18 | JP19 | JP24 | JP25 | JP28 |
AM486SX | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
80486SX | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
CX486DX | 2 & 3 | 1 & 2 | 2 & 3 | 1 & 2, 3 & 4 | Open |
AM486DX | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
80486DX | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
AM486DX2 | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
80486DX2 | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
AM486DX4 | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
80486DX4 | 1 & 2 | 2 & 3 | 4 & 5 | 2 & 3 | 1 & 2 |
Note: Pins designated should be in the closed position. |
CPU TYPE SELECTION (CON’T) | ||||
Type | JP29 | JP33 | JP37 | JP40 |
AM486SX | 3 & 4 | 2 & 3 | Open | 1 & 2 or 2 & 3 |
80486SX | 3 & 4 | 2 & 3 | Open | 1 & 2 or 2 & 3 |
CX486DX | 2 & 3 | 1 & 2 | 3 & 4 | 1 & 2 |
AM486DX | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
80486DX | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
AM486DX2 | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
80486DX2 | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
AM486DX4 | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
80486DX4 | 3 & 4 | 1 & 2, 3 & 4 | 3 & 4 | 1 & 2 or 2 & 3 |
Note: Pins designated should be in the closed position. |
CPU MULTIPLIER SELECTION | |
Multiplier | JP44 |
2x | Pins 1 & 2 closed |
2.5x | Pins 2 & 3 closed |
3x | Open |
CPU VOLTAGE SELECTION | ||
Voltage | Setting | JP80 |
3.45v | UMB on board | Auto detect |
5v | UMB on board | Auto detect |
3.45v | UMB not on board | No support |
5v | UMB not on board | Closed |
VL BUS WAIT STATE SELECTION | |
Setting | JP4 |
0 | Pins 1 & 2 closed |
1 | Pins 2 & 3 closed |
VL BUS SPEED SELECTION | |
Speed | JP3 |
<= 33MHz | Pins 1 & 2 closed |
>33 MHz | Pins 2 & 3 closed |