HP Compaq NX4820 Maintenance And Service Manual page 167

Removal and Replacement Procedures
5. Remove the four PM2.0×3.0 screws 1 that secure the menu
control button board and shield to the top cover.
6. Remove the menu control button board shield 2 and
board 3.
Removing the Menu Control Button Board and Shield
Reverse the above procedure to install the menu control button
board and shield.
5–54 Maintenance and Service Guide