Let's start this review by clearing something up- Arctic Silver 5 is actually composed of 99.9% pure silver. Silver conducts heat excellently, even better than copper, but due to its cost it is no feasible to make heatsinks out of it. Each silver molecule is super small- less than 0.50 microns- so that the thermal compound is able to fit in the microscopic imperfections in the heatsink and processor die as well as creating a near perfect interface between the two surfaces.

Many other thermal compounds claim to be composed of silver but in actuality are only part silver or are simply silver colored. Arctic Silver lists such companies/products as Spire, Titan, Stars 700, CompUSA, OCZ Ultra II, Dynex, Cables Unlimited, Arctic Cooling, and Ultra as saying their products contain between 10% and 90% silver or silver oxide by weight but actually contain no silver at all!

As opposed to being made of silver Ceramique uses "thermally conductive aluminum oxide, boron nitride and zinc oxide sub-micron particles to maximize particle-to-particle contact area and thermal transfer". This mixture is not as thermally conductive as AS5 but can be produced more cheaply and it is said to be nearly as efficient.

Against a generic thermal compound Arctic Silver states that AS5 will be able to keep the processor 3-12° C cooler while Ceramique will keep it 2-10° cooler, at full load temperature. As you are probably thinking- that is a pretty incredible claim.