Dell OptiPlex 755 User's Guide - Page 216

8 When the processor is fully seated in the socket, close the processor cover. Ensure that the tab on the processor cover is positioned underneath the center cover latch on the socket. 9 Pivot the socket release lever back toward the socket and snap it into place to secure the processor. 10 Clean the thermal grease from the bottom of the heat sink. NOTICE: Ensure that you apply new thermal grease. New thermal grease is critical for ensuring adequate thermal bonding, which is a requirement for optimal processor operation. 11 Apply the new thermal grease to the top of the processor. 12 Install the heat sink assembly: a Place the heat sink assembly back onto the heat-sink assembly bracket. b Rotate the heat sink assembly down towards the computer base and tighten the two captive screws. NOTICE: Ensure that the heat sink is correctly seated and secure. 1 2 3 1 heat sink assembly 2 heat-sink assembly bracket 3 captive screw in housing (2) 13 Replace the computer cover (see "Replacing the Computer Cover" on page 317). 216 Processor