Lenovo ThinkCentre 3656 Hardware Maintenance Manual page 136

This section provides information on how to remove and replace the
microprocessor.
To remove or replace the microprocessor, do the following:
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Hardware Maintenance Manual
1. Remove the cover. See "Removing the cover" on page 117.
2. Lift the fan duct off the heat sink fan.
3. Disconnect the heat sink and fan assembly cable from the system board. See
"Locating parts on the system board" on page 119.
4. Rotate handle 1 to release the heat sink clamp and then disengage the
clamp from the plastic retention bracket.
5. Lift the heat sink and fan assembly off the system board. Place the heat sink
on its side so that the thermal grease does not come in contact with anything.
Note: You might have to gently twist the heat sink to free it from the
microprocessor.