How to Choose the Best Thermal Paste for Your CPU

Thermal paste is an essential part of any PC build. It allows your CPU-cooler to do its job by transferring heat from the processor to the cooler, where it can be thrown away into the air. Without it, your computer would constantly overheat and shut down. But not all thermal pastes are created equal. Some are better at transferring heat, some last longer, and some are easier to apply. That’s why we did the hard work to find the best ones on the market.

The best thermal pastes have a base matrix and a filler that increases its thermal conductivity. Typical matrix materials include epoxies, silicones, and urethanes; the fillers can be carbon micro-particles, zinc oxide, aluminum oxide, or boron nitride. The higher the filler content, the greater the thermal conductivity.

In order to be effective, the thermal paste must be dense enough to prevent a “smear” effect on the surface of the processor core(s). It must be easy to apply evenly, fill gaps, and resist degradation under normal usage (which includes thousands of hours of heating cycles) without pumping out or separating.

Gelid GC-Extreme is a good example of a high quality thermal paste that meets all these requirements. It has a moderately viscous compound that is stable during application and spreads consistently. It also has good adherence to the surface of the CPU and doesn’t leak.