HP ProLiant ML110 Gen9 Maintenance And Service Manual page 45

Remove the heatsink from the processor backplate.
c.
To replace the component:
Clean the old thermal grease from the processor with the alcohol swab. Allow the alcohol to evaporate
1.
before continuing.
Remove the thermal interface protective cover from the heatsink.
2.
Install the heatsink:
3.
Position the heatsink on the processor backplate.
a.
Tighten one pair of diagonally opposite screws halfway, and then tighten the other pair of screws.
b.
Removal and replacement procedures 45