Maybe it's just the geek in me...
Most modern desktop CPUs produce an exorbitant ammount of waste heat in their operation--so much so that that without the aid of cooling devices, a CPU core will soon become too hot to operate and may even be damaged.

The heat sink is the first piece of an air-cooling solution. A 'giant block' of thermally conductive metal much larger than the CPU, it serves to conduct heat away from the surface of the processor. It's larger body allows it to 'absorb' a greater deal heat, and the many thin 'fins' at the top increases the ammount of surface area exposed to a heatsink-fan mounted above. In order to be effective though, the heatsink must make 'optimum' contact with the surface of the CPU.

Even with 'smooth' surfaces on the heatsink and CPU, millions of microscopic pits and grooves decorate the face of each piece. In some cases there may even be noticble uneveness resulting in contact seperation. This is where thermal compound comes in. A thin layer of 'non-evaporating' thermally conductive'grease' is smeared between the processor and the heatsink to bridge as many gaps as possible' Applied properly, the thermal compound should be the only thing (i.e. no air pockets) between the CPU and the heatsink.

Boys and girls,



Please do NOT use Velcro between your CPU and your heatsink. :D