Do not open your computer or attempt any repair before reading and understanding the "Important safety information" in the ThinkCentre Safety and Warranty Guide that came with your computer. To obtain a copy of the ThinkCentre Safety and Warranty Guide, go to:http://www.lenovo.com/support
This section provides instructions on how to open the computer cover.
CAUTION:
Turn off the computer and wait three to five minutes to let the computer cool before removing the computer cover.
To open the computer cover, do the following:
Remove all media from the drives. Then, turn off all attached devices and the computer.
Disconnect all power cords from electrical outlets.