c. If the new heat sink did not come with thermal grease, apply thermal grease
on the microprocessor before you install the heat sink (see “Thermal
grease”).
d. Align the heat sink above the microprocessor with the thermal grease side
down.
e. Slide the flange of the heat sink into the opening in the retainer bracket.
f. Press down firmly on the heat sink until it is seated securely.
g. Rotate the heat-sink release lever to the closed position and hook it
underneath the lock tab.
6. Replace the components that you removed in “Removing a microprocessor and
heat sink” on page 216:
v Microprocessor 1: DIMM air baffle and PCI riser-card assembly 1 (see
“Installing the DIMM air baffle” on page 178 and “Installing a PCI riser-card
assembly” on page 168)
v Microprocessor 2: Microprocessor 2 air baffle and PCI riser-card assembly 2
(see “Installing the microprocessor 2 air baffle” on page 176 and “Installing a
PCI riser-card assembly” on page 168).
7. Install the cover (see “Completing the installation” on page 227).
8. Slide the server into the rack.
9. Reconnect the external cables; then, reconnect the power cords and 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.
5. Use the thermal-grease syringe to place nine uniformly spaced dots of 0.02 mL
1 each on the top of the microprocessor 2.
220 ThinkServer RD220 Types 3729, 3779, 3797, and 3798: Hardware Maintenance Manual