Lenovo x3650 M4 BD 5466 Installation And Service Manual page 81

Figure 56. Heat-sink installation
a. Remove the plastic protective cover from the bottom of the heat sink.
b. Align the screw holes on the heat sink with the holes on the system board.
c. Place the heat sink on the microprocessor with the thermal-grease side down.
d. Press firmly on the captive screws and tighten them with a screwdriver. The follow illustration
shows the sequence in tightening the screws, which is also shown on top of the heat sink.
Begin with the screw labeled as "1", then "2", "3" and finally "4". If possible, each screw
should be rotated two full rotations at a time. Repeat until the screws are tight. Do not
overtighten the screws by using excessive force. If you are using a torque wrench, tighten the
screws to 8.5 Newton-meters (Nm) to 13 Nm (6.3 foot-pounds to 9.6 foot-pounds).
Note: Please use Phillips screw driver No.0 to fasten screws.
Figure 57. Screws sequence
If you have other devices to install or remove, do so now. Otherwise, go to "Completing the installation"
on page 73.
.
Chapter 2 Installing optional devices
67