Lenovo ThinkCentre M79 Hardware Maintenance Manual page 135

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. Remove any media from the drives and turn off all attached devices and the computer. Then, disconnect
all power cords from electrical outlets and disconnect all cables that are connected to the computer.
2. Remove the computer cover. See "Removing the computer cover" on page 105.
3. Pivot the drive bay assembly upward. Then, pivot the two plastic retaining clips outward to remove
the heat sink fan duct from the failing heat sink and fan assembly.
Figure 43. Removing the heat sink fan duct
4. 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 34.
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Chapter 11 Installing or replacing hardware
127