THERMAL COMPOUNDS

A thermal compound is defined as a semi-fluidic grease that conducts heat several times more efficiently than air. Why is this important? To the naked eye, the mating surfaces of a heat sink and CPU are smooth and flat; but on a microscopic level, they are anything but smooth, with peaks and valleys on both surfaces. And in fact, when the two surfaces are mated, less than one percent of the surface of each entity (the peaks on both the heat sink and CPU) touches the other surface. The result is a great deal of air left between the processor and the heat sink. Air is an extremely poor thermal conductor, and the end result is a CPU that runs hot (causing damage). Thermal compound is used to fill the space between the mating surfaces and help transfer heat from the CPU to the heat sink.