Dell PowerEdge R450 Installation And Service Manual page 61

Figure 55. Installing the processor and heat sink (PHM)
3. Set the Anti-Tilt wires to the locked position (outward position), and then using the Torx T30 tool, tighten the captive nuts
(8 in-lbf) on the heat sink in the order below:
a. In a random order, tighten the first nut three turns.
b. Tighten the nut diagonally opposite to the nut you tighten first.
c. Repeat the procedure for the remaining two nuts.
d. Return to the first nut to tighten it completely.
e. Check all the nuts to ensure they are firmly secured.
Installing and removing system components 61