Lenovo 4223 Computer Hardware User Manual


 
The following table lists the major FRUs shown in Figure 3 “Locating major FRUs and CRUs” on page 57 and
identies which FRUs also are self-service CRUs or optional-service CRUs.
Notes:
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
specic CRU is visible.
Number FRU description
Self-service CRU Optional-service CRU
1
Heat sink and fan assembly
No Yes
2
Internal speaker No Yes
3
Microprocessor No No
4
Optical drive (available in some models)
Yes No
5
Card reader (available in some models)
Yes No
6
Front audio and USB assembly
No Yes
7
Front bezel Yes Yes
8
Hard disk drives Yes No
9
Hard disk drive fan assembly
Yes No
10
Battery Yes No
11
Memory module Yes No
12
Peripheral Component Interconnect (PCI) card
retainer
Yes No
13
PCI card
Yes No
14
Rear fan assembly
No Yes
15
System board
No No
16
Power supply assembly No No
17
Keyboard Yes No
18
Mouse Yes No
Looking up FRU information
For detailed FRU information, such as the FRU part numbers and supported computer models, go to:
http:/www.lenovo.com/serviceparts-lookup
Locating parts on the system board
Figure 4 “System board part locations” on page 59 shows the locations of the parts on the system board.
58 ThinkStation Hardware Maintenance Manual