Dell Dimension 8300 - Manual (Page 27)

b. Pull the release lever out until the heat sink is released.
c. Lift the heat sink away from the microprocessor.
11. Remove the microprocessor from the socket.
Leave the release lever extended in the release position so that the socket is ready for the new microprocessor.
NOTICE: Lay the heat sink down with the thermal grease facing upward.
NOTICE: If you are installing a microprocessor upgrade kit from Dell™, discard the original heat sink. If you are not installing a microprocessor upgrade
kit from Dell, reuse the original heat sink and blower when you install your new microprocessor.
NOTICE: Be careful not to bend any of the pins when you remove the microprocessor from the socket. Bending the pins can permanently damage the
microprocessor.