Lenovo ThinkStation P720 Hardware Maintenance Manual page 211

7. Apply appropriate amount of thermal grease to the following area on the bottom of the new heat-sink-
and-fan assembly.
Figure 192. Applying thermal grease to the new heat-sink-and-fan assembly
8. Install the microprocessor retainer with the microprocessor to the new heat-sink-and-fan assembly. See
"Microprocessor" on page 207.
9. To install a new heat-sink-and-fan assembly, do the following:
a. Position the new heat-sink-and-fan assembly on the system board. Ensure that:
• The fan on the heat-sink-and-fan assembly is facing the rear of the chassis.
• The two mounting studs on the system board are aligned with the holes in the heat-sink-and-fan
assembly.
• The four screws are aligned with the holes in the system board.
b. Use a T-30 Torx screwdriver to tighten the four screws to secure the new heat-sink-and-fan
assembly to the system board in the following sequence. Do not over-tighten the screws.
1) Fully tighten screw
2) Partially tighten screw
1 , and then fully tighten screw
3 , fully tighten screw
2 .
4 , and then fully tighten screw
.
Chapter 9 Hardware removal and installation
3 .
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