HP Dx5150 - Compaq Business Desktop Reference Manual page 125

To install a processor backing plate:
1. Lay the new system board top down on a padded surface to protect the board from damage.
2. Remove the protective paper shield 1 from the mounting surface of the backing plate.
3. Position the mounting plate studs over the back of the system board 2 and press the plate
firmly to the system board so the studs penetrate the mounting holes.
Complete the installation of the system board by reversing the removal procedures.
Service Reference Guide, dx5150
Removal and Replacement Procedures— Small Form Factor (SFF) Chassis
361685-001 7–31