Maintenance & Service Guide
Presario 7800 Series and 5900T Personal
Computers
Presario 7800 and 5900T Models with Pentium III System Board
Jumper & Switch Information
| Number | Function | Description | Reference Designator |
| 1 | Secondary IDE Drive | 40-pin | J13 |
| 2 | Diskette Drive | 34-pin | J14 |
| 3 | Primary IDE Drive | 40-pin | J12 |
| 4 | Not used | ||
| 5 | Secondary fan connector | J20 | |
| 6 | Button Board | 20-pin | J10 |
| 7 | CMOS | 3-pin | JP1 |
| 8 | Battery Socket | Battery holder | BT1 |
| 9-13 | PCI Slots | 32-bit PCI connector | PCI 1 to 5 |
| 14 | AGP Slot | Connector | AGP1 |
15 |
Slot 1 | 321-pin PGA | J18 |
| 16 | Front side bus | four, 2-pin jumpers | JP5-7* |
| 17 | Heat sink fan connector | 3-pin | J15 |
| 18-20 | DIMM Sockets | 168-pin DIMM | DIMM 1 to 3 |
| 21 | IEEE 1394 | 10-pin | JP3 |
| 22 | Front I/O panel | 10-pin | JP4 |
| 23 | Single front I/O panel | 30-pin | J11** |
| 24 | Mouse | Miniature 6-pin | J1 |
| 25 | Keyboard | Miniature 6-pin | J1 |
| 26 | Back USB | Dual 4-pin | J2 |
| 27 | Serial Port | DSUB 9-pin | J4 |
| 28 | Parallel Port | DSUB 25-pin | J21 |
| 29 | IEEE 1394 Connector | 6-pin | J7 |
| Fan | 3-pin | ||
| Power Supply | 20-pin | J9 | |
| Clock Multiplier | 3, 2-pin | JP2 |
* JP7 always set to the ON position. JP5, JP6, and JP8 always set to the OFF
position.
** Single front I/O panel and USB and IEEE1394 connectors are not used concurrently.
Jumper Settings
| CMOS Normal | CMOS Clear |
| pins 1-2 | pins 2-3 |
| Multiplier | Pin (1-2) | Pin (3-4) | Pin (5-6) | Pin (7-8) | FSB 66 MHz | FSB 100 MHz | FSB 133 MHz |
| 2 | ON | ON | ON | ON | 133 | 200 | 266 |
| 3 | ON | OFF | ON | ON | 200 | 300 | 400 |
| 4 | OFF | ON | ON | ON | 266 | 400 | 533 |
| 5 | OFF | OFF | ON | ON | 333 | 500 | 667 |
| 5/2 | ON | ON | OFF | ON | 166 | 250 | 333 |
| 7/2 | ON | OFF | OFF | ON | 233 | 350 | 466 |
| 9/2 | OFF | ON | OFF | ON | 300 | 450 | 600 |
| 11/2 | OFF | OFF | OFF | ON | 366 | 550 | 733 |
| 6 | ON | ON | ON | OFF | 400 | 600 | 800 |
| 7 | ON | OFF | ON | OFF | 466 | 700 | 933 |
| 8 | OFF | ON | ON | OFF | 533 | 800 | 1066 |
| Reserved | OFF | OFF | OFF | OFF | *** | *** | *** |
| 13/2 | ON | ON | OFF | OFF | 433 | 650 | 866 |
| 15/2 | ON | OFF | OFF | OFF | 500 | 750 | 1000 |
| 3/2 | OFF | ON | OFF | OFF | 100 | 150 | 200 |
| 2 | OFF | OFF | OFF | OFF | 133 | 200 | 266 |
