Dell PE R720XD Owner's Manual page 81

Figure 44. Removing and Installing the Processor Heat Sink
1. heat sink
2. retention sockets (2)
3. retention screws (2)
4. processor
CAUTION: The processor is held in its socket under strong pressure. Be aware that the release lever can spring up
suddenly if not firmly grasped.
8.
Position your thumb firmly over the processor socket-release lever near the unlock icon
from the locked position by pushing down and out from under the tab.
9.
Similarly, position your thumb firmly over the processor socket-release lever near the lock icon
lever from the locked position by pushing down and out from under the tab. Rotate the lever 90 degrees upward.
and release the lever
and release the
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