NEC Express5800 User Manual page 417

IMPORTANT:
sink is installed incorrectly, you will fail to install the CPU duct.
3.
Secure the heat sink with four screws.
Temporarily tighten the four screws on cater corner, then tighten them securely after
making sure that the heat sink has been seated.
4.
Make sure that the heat sink is level with the mother board.
IMPORTANT:
If the heat sink is not level, remove it, and then install it again. The

following probably causes the heat sink not to be level:
– The CPU is not positioned correctly.
– All screws are not completely tightened.
Do not move the secured heat sink.

Removal
Remove the heat sink from the CPU in the reverse procedure of the installation.
Be aware of orientation of the heat sink. If the heat
Upgrading Your Server 9-79