Artic Silver III, is definitely #1 in my book, its been an outperformer, in every situation I've used it, regarding your question, one point to leave you with is that, you use just enough to thinly cover the DIE or(Core), by about the thickness of a very thin sheet of paper, the thinner the better, smooth and even as possible. I've seen guys in computer shops just squirt the compound on the CPU, and press the heatsink into the compound, you would think those guys know what they're doing, but they don't. The purpose of the compound is to fill the imperfections between the die and the heatsink and thats all, you'll actually get less performance from too much heatsink compound.
Now the (2 Part), Artic Silver Thermal Compound,(<b>Adhesive</b>), not the CPU Polysynthetic compound, will conduct electricity, theres warnings at the Artic Silver website about it, and how to use it, but thats for installing small heatsinks to video card RAM, and various chipsets, or any situation where you can't have hold down clamps, or some type of securing methods to keep the heatsink in place.
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