IBM x3550 - System - 7978, Problem Determination And Service Manual

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Heat sink
Heat-sink
installation
label
Microprocessor
Thermal grease
4. If the new heat sink did not come with thermal grease, you must apply thermal
grease on the microprocessor before you install the heat sink (see “Thermal
grease”).
5. Install the heat sink on top of the microprocessor, and tighten the captive
screws. Alternate among the screws on either side of the heat sink until they are
snug, and then alternate again until they are tight, making sure that you do not
overtighten any of them.
Attention: Do not touch the thermal grease on the bottom of the heat sink or
set down the heat sink after the plastic cover is removed. Touching the thermal
grease will contaminate it.
6. Install the cover (see “Installing the cover” on page 42).
7. Slide the server into the rack.
8. Reconnect the power cords and any cables that were removed.
9. Turn on the peripheral devices and the server.
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.
To replace damaged or contaminated thermal grease on the microprocessor and
heat exchanger, complete the following steps:
1. Place the heat sink assembly on a clean work surface.
2. Remove the cleaning pad from its package and unfold it completely.
3. Use the cleaning pad to wipe the thermal grease from the bottom of the heat
exchanger.
Note: Make sure that all of the thermal grease is removed.
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.
Chapter 4. Removing and replacing server components
89