Thermal Grease is a liquid substance used to fill the microscopic gaps between an IC chip’s heat spreader and the heat sink, improving the thermal transfer from one surface to another. It’s an essential component of modern computing, as CPUs generate a lot of heat that must be dissipated to avoid overheating and damage.
It is usually sold in tubes at electronics stores, along with a small shovel-like tool called an applicator to help you apply it. Some hardware enthusiasts swear by it, and even overclockers will often use it to increase their processor’s speed by lowering its operating temperature.
Some types of thermal grease are more viscous than others. This is because they have a higher concentration of metallic compounds (such as silver, copper or aluminum), which make them more effective at conducting heat between surfaces. However, this higher concentration of metal also increases the risk of electrical shorting if the liquid spills onto the pins or components of a motherboard, which could fry your computer.
Other types of thermal paste are less viscous, which makes them safer and easier to apply for beginners. Some even claim to be completely non-conductive, meaning that you can safely slosh it around and not worry about accidentally shorting any components. These typically consist of silicone oil compounds that are mixed with different levels of thermally conductive fillers.