HPE ProLiant DL160 Gen10 Maintenance And Service Manual page 94

2. Remove the processor heatsink dust cover.
Reinstall the dust cover on failed system board.
3. Install the processor heatsink assembly:
a. Locate and align the Pin 1 indicator on the processor frame and the socket.
b. Align the processor heatsink assembly with the heatsink alignment posts and gently lower it down until it sits evenly on the socket.
The heatsink alignment posts are keyed. The processor will only install one way.
A standard heatsink is shown, your heatsink might look different.
HPE ProLiant DL160 Gen10 Server Maintenance and Service Guide 94