Before placing the heatsink, it is extremely important that you place thermal paste on the new cpu. Thermal paste allows for heat to be conducted from your cpu to the heatsink and out of the computer, without this your cpu may become damaged or broken.

Follow this guide to replace your thermal paste, the heatsink is pictured to the left. You will need to remove the grey paste from the right end of the heatsink.

How to Apply Thermal Paste