Dell OptiPlex 390 (Mid 2011) - Manual (Page 29)

Heat Sink And Processor
10
Removing the Heat Sink and Processor
1. Follow the procedures in Before Working Inside Your Computer .
2. Remove the cover .
3. Disconnect the heat sink assembly cable from the system board.
4. Loosen the captive screws that secure the heat sink assembly to the
system board.
5. Lift the heat sink assembly upwards and remove it from the computer. Lay
the assembly with the fan facing downwards, and with the thermal grease
facing upwards.
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