Lenovo System x3650 M4 Installation And Service Manual page 349

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 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 34.
• Read "Handling static-sensitive devices" on page 36.
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.
Step 3. Use the cleaning pad to wipe the thermal grease from the bottom of the heat sink.
Note: Make sure that all of the thermal grease is removed.
Step 4. Use a clean area of the cleaning pad to wipe the thermal grease from the microprocessor; then,
dispose of the cleaning pad after all of the thermal grease is removed.
Step 5. Use the thermal-grease syringe to place 9 uniformly spaced dots of 0.02 mL each on the top of
the microprocessor. The outermost dots must be within approximately 5 mm of the edge of the
microprocessor; this is to ensure uniform distribution of the grease.
Figure 254. Thermal grease distribution
Note: If the grease is properly applied, approximately half of the grease will remain in the syringe.
0.02 mL of thermal
Microprocessor
Chapter 6
grease
.
Removing and replacing components
337