Lenovo ThinkCentre M90p, Maintenance Manual, Page: 85 / 112

1. Turn off the computer and disconnect all power cords from electrical outlets.
2. Open the computer cover. See “Opening the computer cover” on page 68.
3. Pivot the optical drive bay assembly upward.
4. Remove the hard disk drive to access the heat sink. See “Replacing the hard disk drive” on page 84.
5. Carefully remove the four screws 1 that secure the heat sink to the system board.
Note: Carefully remove the four screws from the system board to avoid any possible damage to the
system board. The four screws cannot be removed from the heat sink.
Figure 16. Removing the heat sink
6. Carefully lift the heat sink off the system board.
Notes:
a. You might have to gently twist the heat sink to free it from the microprocessor.
b. Do not touch the thermal grease while handling the heat sink.
7. Position the new heat sink on the system board so that the four screws are aligned with the holes
on the system board.
8. Alternate tightening each screw a small and equal amount until the heat sink is secured to the system
board. Do not over-tighten the screws.
9. Go to “Completing the parts replacement” on page 93.
Replacing the microprocessor
Attention
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 replace the microprocessor.
Chapter 8
.
Replacing FRUs (Machine type: 7536)
79