Lenovo 5548 Personal Computer User Manual


 
CAUTION:
The heat sink 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 heat sink, do the following:
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 12.
3. Pivot the optical drive bay assembly upward. See “Accessing the system board components and drives”
on page 12.
4. Remove the hard disk drive to access the heat sink. See “Replacing the hard disk drive” on page 18.
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 24. 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.
What to do next:
To work with another piece of hardware, go to the appropriate section.
To complete the installation or replacement, go to “Completing the parts replacement” on page 32.
Chapter 2. Installing or replacing hardware 25