HP zx5000 - Manual (Page 131)

5–24 Maintenance and Service Guide
Removal and Replacement Procedures
8. Remove the 4 PM2.5×11.0 spring-loaded shoulder
screws that secure the heat sink to the notebook.
Removing the Heat Sink Screws
✎
When reinstalling the heat sink screws, first start all
4 screws but do not tighten them. After all 4 screws are
started, tighten each screw until the shoulder on the screw
is fully seated against the screw post. Tighten the screws
diagonally across the heat sink, not in sequence around the
heat sink.