Fru Replacement Notices; Screw Notices - IBM ThinkPad X20 Hardware Maintenance Manual

FRU replacement notices

This section contains notices related to removing and
replacing parts. Read this section carefully before replacing
any FRU.

Screw notices

Loose screws can cause a reliability problem. The IBM
ThinkPad computer addresses this problem with special
nylon-coated screws that have the following characteristics:
v They maintain tight connections.
v They do not easily come loose, even with shock or
vibration.
v They are harder to tighten.
v They should be used only once.
Do the following when you service this machine:
v Keep the screw kit (P/N 05K4841) in your tool bag.
v Always use new screws.
v Use a torque screwdriver if you have one.
Tighten screws as follows:
v Plastic to plastic
Turn an additional 90 degrees after the screw head
touches the surface of the plastic part:
90 degrees more
(Cross section)
v Logic card to plastic
50
ThinkPad X20, X21, X22