Dell XPS 8300 Service Manual page 87

CAUTION:
Ensure that you apply new thermal grease. New thermal grease is
critical for ensuring adequate thermal bonding, which is a requirement for optimal
processor operation.
9 Apply the new thermal grease to the top of the processor.
10 Replace the processor fan and heat-sink assembly (see "Replacing the
Processor Fan and Heat-Sink Assembly" on page 81).
CAUTION:
Ensure that the processor fan and heat-sink assembly is correctly
seated and secure.
11 Replace the computer cover (see "Replacing the Computer Cover" on
page 18).
12 Connect your computer and devices to electrical outlets, and turn them on.
Processor
87