Lenovo System x3250 M5 Installation And Service Manual page 258

Figure 171. Heat sink installation
Step 5. Install the heat sink on the microprocessor.
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.
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.
Step 6. Reinstall the air baffle if it was removed before (see "Replacing the air baffle" on page 160).
Step 7. Reinstall the cover (see "Replacing the cover" on page 158).
What to do next
1. Install the server into the rack enclosure and push the server into the rack until it clicks into place.
2. Reconnect the power cords and any cables that you removed.
3. 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. Use this information to
replace damaged or contaminated thermal grease on the microprocessor and heat sink.
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Lenovo System x3250 M5Installation and Service Guide