HP Evo D510 SFF Hardware Reference Manual page 16

Hardware Upgrades
2–4
To open the computer cover:
1. Turn off the computer and any external devices.
2. Disconnect the power cord from the power outlet, and disconnect
any external devices.
3. Using the Smart Cover FailSafe Key, remove the two
tamper-proof screws that secure the Smart Cover Lock to the
chassis.
Removing the Smart Cover Lock Screws
4. Remove the Smart Cover Lock.
To reattach the Smart Cover Lock, secure the lock in place with the
tamper-proof screws.
Hardware Reference Guide