Lenovo System x3630 M4, Installation And Service Manual

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Heat sink
c. 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).
If you have other devices to install or remove, do so now. Otherwise, go to “Completing the installation”
on page 87.
Thermal grease
The thermal grease must be replaced whenever the heat sink has been removed from the top of the
microprocessor and is going to be reused or when debris is found in the grease. Use this information to
replace damaged or contaminated thermal grease on the microprocessor and heat sink.
When you are installing the heat sink on the same microprocessor that is was removed from, make sure
that the following requirements are met:
• The thermal grease on the heat sink and microprocessor is not contaminated.
• Additional thermal grease is not added to the existing thermal grease on the heat sink and microprocessor.
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Lenovo System x3630 M4 Installation and Service Guide