Dell XPS 730 (Late 2008) - Manual (Page 89)

Replacing the System Board 87
9 Orient the system board assembly by aligning the notches on the bottom
of the assembly with the tabs on the computer.
10 Slide the system board assembly toward the back of the computer until the
assembly clicks into place.
11 Replace the two screws to secure the system board assembly to the chassis.
12 Replace any expansion cards that you removed (see "Replacing a PCI/PCI
Express Card" on page 27).
13 Replace any additional components that you removed from the system
board.
14 Reconnect all cables to the system board.
15 Replace the computer cover (see "Replacing the Computer Cover" on
page 17).
16 Connect your computer and devices to electrical outlets, and then turn
them on.
17 Flash the system BIOS, as needed.
NOTE: For information on flashing the system BIOS, see support.dell.com.