Thermal Grease - Lenovo System x3550 M4 Installation And Service Manual

Figure 73. Heat sink installation
c. Align and place the heat sink on top of the microprocessor in the retention bracket, thermal
material side down.
d. Press firmly on the heat sink.
e. Rotate the heat sink retention module release lever to the closed position and hook it
underneath the lock tab.
Step 11. If you installed the second microprocessor, install the fourth and sixth fans (see "Replacing a hot-
swap fan" on page 244).
If you have other devices to install or remove, do so now. Otherwise, go to "Completing the installation" on
page 86.

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.
When you are installing the heat sink on the same microprocessor that it 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.
Notes:
• Read the safety information that begins on "Safety" on page v.
• Read the "Installation guidelines" on page 31.
• Read "Handling static-sensitive devices" on page 33.
To replace damaged or contaminated thermal grease on the microprocessor and heat sink, complete the
following steps:
Step 1. Place the heat sink on a clean work surface.
Step 2. Remove the cleaning pad from its package and unfold it completely.
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Lenovo System x3550 M4 Installation and Service Guide