Thermal Grease - IBM x3250 M3 Problem Determination And Service Manual

10. Connect the cables and power cords.
11. Turn on all attached 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.
When you are installing the heat sink on the same microprocessor that it was
removed from, make sure that the following requirements are met:
v The thermal grease on the heat sink and microprocessor is not contaminated.
v Additional thermal grease is not added to the existing thermal grease on the heat
Note:
1. Read the safety information that begins on page vii.
2. Read "Installation guidelines" on page 127.
3. Read "Handling static-sensitive devices" on page 129.
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IBM System x3250 M3 Types 4251, 4252, and 4261: Problem Determination and Service Guide
Attention: Do not touch the thermal material on the bottom of the heat sink.
Touching the thermal material will contaminate it. If the thermal material on the
microprocessor or heat sink becomes contaminated, contact your service
technician.
a. Make sure that the thermal material is still on the bottom of the heat sink;
then, align the heat sink so that the arrows on the label point toward the
DIMMs and place the heat sink on top of the microprocessor, thermal
material side down.
Heatsink
Orientation
DIMMs
DIMMs
b. Align the screws on the heat sink with the screw holes on the system
board.
c. Tighten the screws with a screwdriver, alternating among the screws until
they are tight. 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.
Attention: When the two screws that are closer to the rear of the server
are tightened, the screw heads are not level with the surface of the heat
sink. Do not overtighten the screws by using excessive force.
7. Replace the air baffle (see "Installing the DIMM air baffle" on page 133).
8. Install the cover (see "Installing the cover" on page 130).
9. Slide the server into the rack.
sink and microprocessor.