Dell Vostro 400 (Mid 2007) - Manual (Page 161)

Removing and Installing Parts
161
9 Clean the thermal grease from the bottom of the heat sink.
NOTICE:
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.
10 Apply the new thermal grease to the top of the processor.
11 Install the processor fan/heat sink assembly (see "Installing the Processor
Fan/Heat Sink Assembly" on page 157).
NOTICE:
Ensure that the processor fan/heat sink assembly is correctly seated and
secure.
12 Replace the computer cover (see "Replacing the Computer Cover" on
page 166).
1 processor cover 2 tab 3 processor
4 processor socket 5 center cover latch 6 release lever
7 front alignment-notch 8 processor pin-1 indicator 9 rear alignment notch
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