HP (Hewlett-Packard) NX9020 ユーザーズマニュアル

This chapter provides removal and replacement procedures.

There are 77 screws and screwlocks, in 11 different sizes, that 
must be removed, replaced, or loosened when servicing the 
notebook. Make special note of each screw size and location 
during removal and replacement.

Refer to 

on screw sizes, locations, and usage.

Report the notebook serial number to HP when requesting 
information or ordering spare parts. The serial number is 
located on the bottom of the notebook.