HP ZBook 17 Service Manual page 114

5.
Use the image below that matches your computer's thermal pad configuration.
The thermal material must be thoroughly cleaned from the surfaces of the graphics board heat sink
and the graphics board each time the graphics board heat sink is removed: Thermal material is
used on the system board component closer to the fan (1) and the heat sink that services it (2), as
well as on the graphics board (3) and various locations on the graphics board heat sink section
(4) that services it.
102 Chapter 6 Removal and replacement procedures for Authorized Service Provider parts