Lenovo ThinkCentre M800, Hardware Maintenance Manual, Page: 42 / 178

• Self-service CRUs: These CRUs unplug or are secured by no more than two screws. Examples of
these types of CRUs include the keyboard, the mouse, any USB device, and the power cord. Other
self-service CRUs depending on product design might include memory modules, adapter cards, hard
disk drives, and optical drives.
• Optional-service CRUs: These CRUs are isolated parts within the computer and are concealed by an
access panel that is typically secured by more than two screws. Once the access panel is removed, the
specific CRU is visible.
Number FRU description
Self-service CRU Optional-service CRU
1
Computer cover
Yes No
2
Optical drive bracket Yes No
3
Optical drive Yes No
4
Power supply assembly No Yes
5
Secondary storage drive Yes No
6
Secondary storage drive bracket Yes No
7
USB assembly No No
8
Card reader
No No
9
Card reader and USB assembly bracket No No
10
Front audio and USB assembly No No
11
Front Wi-Fi antenna No No
12
Front fan No No
13
Thermal sensor No No
14
Internal speaker No No
15
Cover presence switch (also called intrusion
switch) No No
16
Primary storage drive bracket Yes No
17
Primary storage drive Yes No
18
Chassis No No
19
PCI adapter card
Yes No
20
PCI card Yes No
21
Rear Wi-Fi antenna No No
22
Wi-Fi card No No
23
Wi-Fi adapter card No No
24
PCI Express card
Yes No
25
System board No No
26
Coin-cell battery Yes No
27
Microprocessor No No
28
Memory module Yes No
29
Heat sink fan duct No Yes
30
Heat sink and fan assembly No Yes
31
Front bezel Yes No
32
Power cord Yes No
34
ThinkCentre M800 and M900 Hardware Maintenance Manual