The Importance of Thermal Paste

Thermal paste is the least exciting component in a computer build, but it's also one of the most important. It helps ensure optimal heat transfer between the CPU and the heat sink, which prevents overheating that can lead to throttling and random shutdowns. There are a variety of different brands and formulas available, at various price and performance points. But even the best thermal paste requires care and attention to apply correctly. If not applied properly, a single drop of paste can cause the entire CPU to fry.

The surfaces of the integrated heat spreader (or IHS) on a CPU and the base plate of its heat sink appear smooth, but they actually contain microscopic imperfections that trap air. Air is a poor thermal conductor and hinders maximum heat dissipation. A good quality thermal paste fills these imperfections and improves heat transfer between the CPU and its cooler.

Most thermal pastes consist of a silicon-based binder with either ceramic or metallic particles suspended within it. Zinc oxide is the most common ceramic filler used for traditional thermal paste compounds, which have a thermal conductivity between 2 and 4 W/m*K. For more performance, silver-based compounds use micronized silver to achieve a conductivity of 3 to 8 W/m*K or higher. Liquid metal compounds require a higher level of focus and attention to apply, because they are electrically conductive and can damage circuitry if squeezed out onto the wrong spot.Thermal paste