Lenovo ThinkCentre 3231 Hardware Maintenance Manual page 147

4. Remove the heat sink and fan assembly from the system board by pivoting the
lever 1 securing the heat sink and fan assembly until it is fully in the up
position. Carefully lift the heat sink and fan assembly off the system board.
Note: It helps to remove the hard disk drive before this step. See "Replacing
the hard disk drive" on page 148.
Figure 52. Removing the heat sink and fan assembly
5. Place the new heat sink and fan assembly into position and lower the lever to
secure the heat sink and fan assembly.
6. Connect the heat sink and fan assembly cable to the microprocessor fan
connector on the system board.
7. Go to "Completing the FRU replacement" on page 158.
Chapter 9. Replacing FRUs - Desktop computers
141