Lenovo M91p 4480 User Manual page 63

CAUTION:
The heat sink and fan assembly might be very hot. Turn off the computer and wait three to five
minutes to let the computer cool before removing the computer cover.
To replace the heat sink and fan assembly, do the following:
1. Turn off the computer and disconnect all power cords from electrical outlets.
2. Remove the computer cover. See "Removing the computer cover" on page 32.
3. Lay the computer on its side for easier access to the system board.
4. Locate the heat sink and fan assembly. See "Locating parts on the system board" on page 12.
5. Disconnect the heat sink and fan assembly cable from the microprocessor fan connector on the system
board. See "Locating parts on the system board" on page 12.
6. Follow this sequence to remove the four screws that secure the heat sink and fan assembly to the
system board:
a. Partially remove screw
b. Partially remove screw
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 and fan assembly.
Figure 31. Removing the heat sink and fan assembly
7. Lift the failing heat sink and fan assembly off the system board.
Notes:
a. You might have to gently twist the heat sink and fan assembly to free it from the microprocessor.
b. Do not touch the thermal grease while handling the heat sink and fan assembly.
8. Position the new heat sink and fan assembly on the system board so that the four screws are aligned
with the holes on the system board.
1 , then fully remove screw
3
, then fully remove screw
2 , and then fully remove screw
4
, and then fully remove screw
.
Chapter 5 Installing or replacing hardware
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3
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