Fujitsu PRIMERGY CX2550 M6 Upgrade And Maintenance Manual page 184

Processor (CPU)
Figure 116: Installing the heat sink (C)
▶ Fasten the four captive screws in the sequence printed on the heat sink (1 to
4) by proceeding as follows:
Torque: 0.9 Nm (not used in Japan)
▶ First, fasten the captive screws with 2 - 3 rotation in the sequence 1 to 4.
▶ Fasten the captive screws 1 and 2 completely.
▶ Fasten the captive screws 3 and 4 completely.
184 Upgrade and Maintenance Manual