Dell OptiPlex 390 (Mid 2011) - Manual (Page 27)

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. Remove the front bezel .
4. Remove the drive cage .
5. Disconnect the heat-sink assembly cable from the system board.
6. Release the Input/Output Board or the FlyWire cable from the routing
channel on the heat sink.
7. Loosen the captive screws in the order of 1,2,3 and 4.
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