Lenovo Flex System x220, Installation And Service Manual

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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.
To replace damaged or contaminated thermal grease on the microprocessor and heat sink, complete the
following steps:
Step 1. Place the heat-sink assembly 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.
Microprocessor
0.02 mL of thermal
grease
Step 5. Use the thermal-grease syringe to place nine uniformly spaced dots of 0.02 mL each on the top of
the microprocessor.
Note: 0.01mL is one tick mark on the syringe. If the grease is properly applied, approximately half
(0.22 mL) of the grease will remain in the syringe.
Step 6. Continue with the microprocessor installation instructions in “Installing a microprocessor and
heat sink” on page 678.
Removing the system-board assembly
Use this information to remove the system-board assembly.
Note: This procedure should be performed only by trained service technicians.
Before you remove the system-board assembly, complete the following steps:
1. Read “Safety” on page iii and “Installation guidelines” on page 637.
2. If the compute node is installed in an Flex System chassis, remove it (see “Removing a compute node
from a chassis” on page 639 for instructions).
3. Carefully lay the compute node on a flat, static-protective surface, orienting the compute node with
the bezel pointing toward you.
4. Obtain the following for use during the replacement procedure (see Chapter 5 “Parts listing, Types
2585 and 7906” on page 55).
• Alcohol wipes
Chapter 7
.
Installing, removing, and replacing compute node components
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