HP Nc2400 - Compaq Business Notebook Maintenance And Service Manual page 156

Removal and Replacement Procedures
✎
The thermal paste should be thoroughly cleaned from the surfaces
of the fan/heat sink assembly 1 and processor 2 each time the
fan/heat sink assembly is removed.
The thermal pads should be thoroughly cleaned from the surfaces
of the fan/heat sink assembly 3 and video chip 4 each time the
fan/heat sink assembly is removed.
Thermal paste and thermal pads are included with all fan/heat
sink assembly and processor spare part kits.
Thermal Paste and Thermal Pad Locations
Reverse the above procedure to install the fan/heat sink assembly.
5–64 Maintenance and Service Guide