Dell Precision R5500 Owner's Manual page 49

23. Position your thumb firmly over the processor socket-release lever. Release the lever from the locked position by pushing down and
pulling out from under the tab.
24. Rotate the lever 90 degrees upward until the processor is released from the socket. Rotate the processor shield upward and remove
it.
25. Carefully lift the processor out of the socket.
26. Repeat steps 21 to 25 for the second processor (if installed).
Processor and Heat Sink 49