IBM System x3650 M4 BD Type 5466 Installation And Service Manual page 265

Figure 175. Heat-sink installation
a. Remove the plastic protective cover from the bottom of the heat sink.
b. Align the screw holes on the heat sink with the holes on the system board.
c. Place the heat sink on the microprocessor with the thermal-grease side
down.
d. Press firmly on the captive screws and tighten them with a screwdriver.
The follow illustration shows the sequence in tightening the screws, which
is also shown on top of the heat sink. Begin with the screw labeled as "1",
then "2", "3" and finally "4". 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. If you are using a torque
wrench, tighten the screws to 8.5 Newton-meters (Nm) to 13 Nm (6.3
foot-pounds to 9.6 foot-pounds).
Note: Please use Phillips screw driver No.0 to fasten screws.
Figure 176. Screws sequence
7. If you are replacing microprocessor 1, install the previously removed memory
module into DIMM connector 6. If you are replacing microprocessor 2, install
the previously removed memory module from DIMM connector 12. See
"Replacing a memory module" on page 187 for instructions.
Chapter 6. Removing and replacing components
249