Insert the tip of a small flathead screwdriver between the X clamp and its retaining post on the heat sink.

Pry the X clamp away from its retaining post until it is lifted above the small groove cut into the retaining post.

If necessary, insert your screwdriver parallel to the motherboard between the X clamp and its retaining post. Twist the screwdriver to fully release the X clamp from its retaining post.

Repeat this process for all four corners of the X clamp.

When removing the last corner of the X clamp and holding the motherboard upside down, be sure to catch the CPU heat sink to avoid damage from it falling.

Remove the CPU heat sink from the motherboard. When reinstalling the CPU heat sink, be sure to apply a new layer of thermal paste.