28 User Guide
Overview
This guide is intended to be used by customers who are replacing Customer
Replaceable Units (CRUs) as well as trained service personnel who are replacing
Field Replaceable Units (FRUs). In this guide, CRUs and FRUs will be referred to as
parts.
Note: Trained service personnel should refer to the Hardware Maintenance
Manual (HMM) for parts ordering information.
This guide does not include procedures for all parts. It is expected that cables,
switches, and certain mechanical parts can be replaced by trained service
personnel without the need for step-by-step procedures.
Note: Use only parts provided by Lenovo™.
The description of the TV card in this manual applies only to machines which have
a TV card. It does not apply to machines which do not have a TV card.
This guide contains procedures for replacing the following parts:
• Memorymodules
• Harddiskdrive
• Opticaldrive
• GraphicCard
• TVTuner
• WLANCard
• Heatsink&Fan
• Keyboard
• Mouse

Safety information for replacing CRUs

Do not open your computer or attempt any repair before reading the “Important
safety information” in the Safety and Warranty Guide that was included with your
computer. If you no longer have this copy of the Safety and Warranty Guide, you
can obtain one online from the Support Web site at http://support.lenovo.com.