Thermal paste is the stuff that helps transfer heat from your processor to your CPU cooler and ultimately out into the air around your PC. Without it, your computer would overheat after only a few minutes of use. The best thermal pastes are high-quality, last for years, and are easy to apply and clean up.
In a basic sense, thermal paste is a dense compound used to fill any air gaps between the metal surfaces of an electronic component (like a CPU) and the heat sink that dissipates the generated heat. Since metal is a better conductor of thermal energy than air, the gaps between the two must be filled for optimal heat exchange.
Whether it’s to improve an existing CPU or to build your next desktop, the quality of your thermal paste is crucial for the system to work properly. While the best thermal pastes come in a variety of price and performance points, they all function the same.
First, use a lint-free wipe (such as a coffee filter) and some 70% or higher isopropyl alcohol to remove any old thermal grease from the processor surface. Don’t touch the copper or aluminium parts of the heat sink with the IPA, as doing so will likely cause permanent damage. Then, you can apply a small bead of the thermal paste to the processor – the amount needed is variable, but generally it should be around the size of a pea or grain of rice. Avoid applying too much, as this will decrease the thermal efficiency of the paste.