Thermal Interface Materials

Thermal paste fills the microscopic gaps between the processor’s surface and the cooler’s base. Those two surfaces look flat and are not, and air trapped between them is a very poor conductor — the paste displaces it.

How much. A pea-sized blob in the centre, spread by the pressure of mounting the cooler, is the standard method and it works. More is not better: excess paste squeezes out and insulates rather than conducting. This is the most common mistake.

When to replace. If you remove a cooler for any reason, clean both surfaces and apply fresh paste — the old layer will not reseat properly. Otherwise, repasting a machine every few years is worthwhile on a PC that runs hot, since paste dries out over time.

Most new coolers ship with paste pre-applied or in the box, so you may not need a separate tube.

Thermal pads do the same job for components where a gap has to be bridged — memory modules, and M.2 SSD heatsinks such as the ARCTIC M2 Pro, which is worth fitting to a fast PCIe drive.

The range covers ARCTIC, DeepCool and ASUS.