Find the 2 pull tabs and use them to pull out the CPU tray and place them on the table.

Use a hex wrench to unscrew the spring-loaded screw using the star pattern on the CPU Heatsink for even force of the CPU die. This is a specially needed when putting the Heatsink back on.

Turn the hex wrench once each time until it's loose when Using the star pattern (Diagram shown).

On 2009 (4,1) Mac Pros, The CPU comes up with the Heatsink and is not socketed. Like the 2010-2012 (5,1) Mac Pros.

Pull Straight up as there is a vital connection built into the heatsink.

On the bottom of the heatsink will be a copper pad that comes in contact with the CPU. Use a paper towel to wipe off all the remaining thermal paste, isopropyl Alcohol is handy for this.

Isopropyl alcohol is handy for getting the best for cleaning the Copper Heatsink&CPU for new thermal paste.