Lenovo ThinkCentre A58 Hardware Maintenance Manual page 97

CAUTION:
Turn off the computer and wait three to five minutes to let the computer cool
before removing the computer cover.
To remove the computer cover, do the following:
1. Remove any media from the drives. Then, turn off all attached devices and the
computer.
2. Disconnect all power cords from electrical outlets.
3. Disconnect the power cords, Input/Output (I/O) cables, and any other cables
that are connected to the computer.
4. Remove any locking device that secures the computer cover, such as an
integrated cable lock or a padlock.
5. If there are thumbscrews that secure the computer cover, remove the screws.
Chapter 8. Replacing FRUs - Tamdhu
91