Dell XPS 730 (Late 2008) - Manual (Page 81)

Replacing Fans 79
12 Replace the computer cover (see "Replacing the Computer Cover" on
page 17).
13 Connect your computer and devices to electrical outlets, and then turn
them on.
Replacing the Processor Fan Assembly
1 Remove the card slot fan shroud (see "Removing the Card Slot and
Processor Fan Shrouds" on page 77).
1 processor fan shroud 2 captive screws (2)
2
1