Lenovo 4485 Computer Hardware User Manual


 
12. Reinstall the heat sink and fan assembly with the fan duct as shown. See “Replacing the heat sink and
fan assembly” on page 139.
Figure 88. Reinstalling the heat sink and fan assembly with the fan duct
13. Reconnect all cables that were disconnected from the system board.
14. To complete the installation or replacement, go to “Completing the parts replacement” on page 160.
Replacing the system board
Attention:
Do not open your computer or attempt any repair before reading and understanding the “Important safety information”
in the ThinkCentre User Guide. To obtain a copy of the ThinkCentre User Guide, go to:
http://www.lenovo.com/ThinkCentreUserGuides
This section provides instructions on how to replace the system board.
CAUTION:
The heat sink and microprocessor might be very hot. Turn off the computer and wait three to ve
minutes to let the computer cool before opening the computer cover.
To replace the system board, do the following:
1. Remove all media from the drives and turn off all attached devices and the computer. Then, disconnect
all power cords from electrical outlets and disconnect all cables that are connected to the computer.
2. Open the computer cover. See “Opening the computer cover” on page 121.
3. Remove the front bezel. See “Removing and reinstalling the front bezel” on page 122.
150 ThinkCentre Hardware Maintenance Manual