User Guide

Removing the System Board: Dell Dimension P133a, P166a, M166a, M200a, and M233a

1. Disconnect any cables attached to the I/O panel on the back of the system unit.
2. Remove any installed expansion cards.
   Note the location of each connector and the orientation of any cables attached to the expansion cards before disconnecting these cables.
3. Remove the 3.5-inch diskette drive and the secondary hard-disk drive.
4. Disconnect all internal cables from the system board.
   The cables attached to the PRI IDE, SEC IDE, and FLOPPY connectors each have 2 latches securing them to the system board. Press the latch on each end of the cable connector, and pull to release the cable from the system board.
5. Determine how the system board is mounted in the system unit (see the following figures). If the system board is secured by 5 screws, proceed to step 6. If the system board is secured by hooked standoffs, skip to step 8.

6. Remove the 5 screws that secure the system board to the system unit.
7. Carefully lift the system board out from the I/O gasket, and remove the board from the computer. Then skip to step 11.
8. If the system board is secured with hooked standoffs, remove the mounting screw from the back of the computer.

9. Grasp the 2 front corners of the system board and lift the board slightly to free it from the plastic standoff in the left-front corner of the board. Then slide the system board toward the front of the system unit slightly to free the board from the hooked standoffs, and lift the system board out of the chassis.
10. Remove the mounting bracket from the back of the system board.

11. Remove the microprocessor, DIMMs, and cache card (if present) from the old system board for installation on the replacement board.
    

Before installing the replacement system board, transfer the system-board mounting bracket (for system units with hooked standoffs only), DIMMs, cache card (if present), and microprocessor to the new system board. Also, set the system board jumpers to match the old system board.

When installing a replacement system board, angle the back of the board downward and carefully align the connectors on the back edge of the board with the cutouts in the I/O gasket. When properly aligned, the board connectors slide into the I/O gasket as you seat the board, lowering it into position in the chassis.

For systems with hooked standoffs, press down on the left-front edge of the system board to seat the board firmly over the plastic standoff. Then install the mounting screw.

For systems with 5 mounting screws, continue pushing the system board against the I/O gasket while you secure the board to the chassis with the screws.

CAUTION: Failure to install the system board exactly as described may result in EMI leakage that could interfere with other electronic devices.