Dell Inspiron 1428 (Late 2009) - Manual (Page 41)

Processor Fan and Heat Sink Assembly 41
8 Lift the processor heat sink off the system board.
Replacing the Processor Fan and Heat Sink
Assembly
NOTE: This procedure assumes that you have already removed the processor fan
and heat sink assembly and are ready to replace it.
NOTE: The original thermal pad can be reused if the original processor module and
heat sink are reinstalled together. If either the processor module or heat sink is
replaced, use the thermal pad provided in the kit to ensure that thermal conductivity
is achieved.
1 Follow the procedures in "Before You Begin" on page 9.
2 Place the processor heat sink on the system board.
3 Align the screw holes on the processor heat sink with the screw holes on
the system board and replace the four spring screws in ascending order.
4 Replace the processor fan on the system board.
1 spring screws (4) 2 processor heat sink
1
2