AMERICAN MEGATRENDS, INC.
Omni Business Partner
Processor | 80486SX/80487SX/80486DX/ODP486SX/80486DX2/Pentium Overdrive |
Processor Speed | 20/25/33/50(internal)/66(internal)MHz |
Chip Set | AMI |
Max. Onboard DRAM | 20MB |
Cache | 256KB |
BIOS | AMI |
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 |
IDE interface | J2 | RJ48 10BaseT connector | J35 |
Onboard battery | J5 | SCSI LED | J37 |
PS/2 mouse connector | J6 | Speaker | J38 |
External battery | J8 | Reset switch | J39 |
Serial port 2 | J11 | Turbo switch | J40 |
Secondary cache connector | J12 | BNC 10Base2 connector | J41 |
SCSI connector (internal) | J15 | IDE interface LED | J42 |
Serial port 1 | J16 | Turbo LED | J43 |
SCSI 1 | J17 | Keyboard lock connector | J44 |
VGA port | J31 | Parallel port | P3 |
AUI connector | J32 | Floppy drive interface | P4 |
USER CONFIGURABLE SETTINGS | |||
Function | Jumper/Switch | Position | |
» | PowerGood signal from DS1231 | J1 | Open |
| PowerGood signal not from DS1231 (not installed) | J1 | Closed |
» | Factory configured do not alter | J3 | N/A |
» | Flash ROM programming disabled | J7 | Open |
| Flash ROM programming enabled | J7 | Closed |
» | Factory configured do not alter | J20 | Closed |
» | Video memory DRAM cycle select (6 MCLK RAS) | J21 | Open |
| Video memory DRAM cycle select (7 MCLK RAS) | J21 | Closed |
» | VGA controller IRQ NOT routed to IRQ9 | J22 | Open |
| VGA controller IRQ routed to IRQ9 | J22 | Closed |
» | Enables IRQ12 for onboard PS/2 mouse | J27 | pins 2 & 3 closed |
| Disables IRQ12 for onboard PS/2 mouse | J27 | pins 1 & 2 closed |
» | Enables IRQ10 for NCR SCSI I/O processor | J28 | Closed |
| Disables IRQ10 for NCR SCSI I/O processor | J28 | Open |
» | Enables IRQ11 for onboard LAN controller | J29 | Closed |
| Disables IRQ11 for onboard LAN controller | J29 | Open |
» | VGA onboard controller enabled | J33 | Closed |
| VGA onboard controller disabled | J33 | Open |
» | CMOS memory normal operation | J34 | pins 2 & 3 closed |
| CMOS memory clear | J34 | pins 1 & 2 closed |
» | Onboard SCSI termination chip enabled | J36 | pins 2 & 3 closed |
| Onboard SCSI termination chip disabled | J36 | pins 1 & 2 closed |
» | Factory configured do not alter | SW1/1 | Off |
» | Monitor type select monochrome | SW1/2 | Off |
| Monitor type select color | SW1/2 | On |
| 64KB Cache enabled | SW2/1, 2, 3, 4 | Off |
| 256KB Cache enabled | SW2/1, 2, 3, 4 | On |
SERIAL PORT IRQ CONFIGURATION | ||||
Port 1 (J16) | Port 2 (J11) | J25 | J26 | |
» | IRQ4 | IRQ3 | pins 1 & 2 closed | pins 1 & 2 closed |
| IRQ3 | IRQ4 | pins 2 & 3 closed | pins 2 & 3 closed |
CPU FREQUENCY CONFIGURATION | |||
Frequency | J9 | J10 | |
» | 33 Mhz | Open | Open |
| 25 MHz | Closed | Open |
CPU TYPE CONFIGURATION | ||
CPU Type | J13 | J14 |
80486SX | pins 1 & 2 closed | pins 2 & 3 closed |
80487SX | pins 2 & 3 closed | all closed |
80486DX | pins 1 & 2 closed | all closed |
ODP486SX | pins 2 & 3 closed | all closed |
80486DX2 | pins 1 & 2 closed | all closed |
Pentium Overdrive | pins 2 & 3 closed | all closed |
MEMORY CLOCK SPEED OF THE CLGD5426 | ||
Frequency | J23 | J24 |
50.11 MHz | Closed | Closed |
44.74 MHz | Closed | Open |
41.16 MHz | Open | Closed |
37.58 MHz | Open | Open |
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 |
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 |
10MB | (1) 256K x 36 | (1) 256K x 36 | (1) 1M x 36 | (1) 256K x 36 |
12MB | (1) 1M x 36 | (1) 1M x 36 | (1) 1M x 36 | NONE |
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 |
24MB | (1) 1M x 36 | (1) 1M x 36 | (1) 4M x 36 | NONE |
32MB | (1) 4M x 36 | (1) 4M x 36 | NONE | NONE |
36MB | (1) 1M x 36 | (1) 4M x 36 | (1) 4M x 36 | NONE |
40MB | (1) 1M x 36 | (1) 1M x 36 | (1) 4M x 36 | (1) 4M x 36 |
48MB | (1) 4M x 36 | (1) 4M x 36 | (1) 4M x 36 | NONE |
64MB | (1) 4M x 36 | (1) 4M x 36 | (1) 4M x 36 | (1) 4M x 36 |