Lenovo IdeaCentre B345 All-in-One - Manual (Page 53)

Replacing the CPU
Note: Turn off the computer and wait 3 to 5 minutes to let it cool down before removing the cover.
To replace the CPU
Step 1. Remove any media (disks, CDs, DVDs, or memory cards) from the drives, shut down the operating
system, and turn off the computer and all attached devices.
Step 2. Unplug all power cords from electrical outlets.
Step 3. Disconnect all cables attached to the computer. This includes power cords, input/output (I/O)
cables, and any other cables that are connected to the computer. Refer to “Left and right view”
and “Rear view” for help with locating the various connectors.
Step 4. Remove the rear cover. Refer to “Removing the rear cover”.
Step 5. Remove the computer stand. Refer to “Removing the computer stand”.
Step 6. Remove the optical drive. Refer to “Replacing the optical drive”.
Step 7. Remove the middle cover. Refer to “Removing the middle cover”.
Step 8. Remove the EMI cover. Refer to “Removing the EMI cover”.
Step 9. Remove the system fans. Refer to “Replacing the system fans”.
Step 10. Remove the heat-sink. Refer to “Replacing the heat-sink”.
Step 11. Lift the small handle and open the retainer. 1 2 3
Attention: Do not touch the gold contacts on the bottom of the microprocessor. When handing the
microprocessor, touch only the sides.
Step 12. Lift the microprocessor straight up and out of the socket.
Chapter 8 . Replacing hardware 47