HP Compaq Presario,Presario R4000 Maintenance And Service Manual page 148

Removal and Replacement Procedures
✎
The thermal paste should be thoroughly cleaned from the
surfaces of the thermal module 1 and processor 2 each time
the thermal module is removed. Thermal paste is included with
all thermal module and processor spare part kits.
Thermal Paste Locations
Reverse the above procedure to install the thermal module.
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