Thermal compound, also known as thermal paste or thermal grease, is designed to help transfer heat from a CPU (or any other hot power device) to a heat sink and away from the motherboard and any other heat sensitive components. Without it, the chips would run too hot and eventually burn out or fail due to poor heat dissipation.
While there are non-conductive and conductive thermal compounds, metal-based ones tend to be the best. They contain copper, aluminum and even silver particles that offer the highest thermal conductivity. These materials are usually suspended in an insulating base, often silicone or clay. Most TIMs are easy to use, have good stability and are cheap.
The surfaces of power devices and heat sinks, especially at the microscopic level, are never perfectly flat. This leads to air gaps between the two and reduces their overall thermal efficiency. A quality thermal compound fills these gaps and increases their effectiveness, helping to keep temperatures down and improve performance.
The best thermal compounds have a smooth, creamy consistency that is easily spread and doesn’t dry out quickly. They should also come with a convenient and safe application tool such as a syringe or capillary needle for precise placement. They should also have a screw-on cap to maintain their longevity and prevent drying. A few of our top picks include Noctua’s NH-H1, which offers a nice combination of simple application, easy cleanup and an attractive price per gram. Another great choice is CoolLaboratory Liquid Metal, which comes with a syringe for precision application and a capillary applicator tip to siphon off excess liquid metal.