Lenovo ThinkCentre A58 Hardware Maintenance Manual page 109

5. Remove the four screws 1 that secure the heat sink and fan assembly.
Note: Carefully remove the four screws from the system board to avoid any
possible damage. The four screws cannot be removed from the heat sink
and fan assembly.
Figure 17. Screws that secure the heat sink and fan assembly
6. Lift the old 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. When handling the heat sink and fan assembly, do not touch the thermal
grease on the bottom of the heat sink and fan assembly.
7. Place the new heat sink and fan assembly on the system board so that the four
screws are aligned with the corresponding holes in the system board. Make
sure that you place the new heat sink and fan assembly correctly so that you
can easily connect the heat sink and fan assembly cable to the microprocessor
fan connector on the system board.
Chapter 8. Replacing FRUs - Tamdhu
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