> For example, the thermal conductivity of a high-grade thermal paste is 8.5 W/mK, and the heat conductivity of copper is 385 W/mK, or for aluminum 205 W/mK. Yo

> For example, the thermal conductivity of a high-grade thermal paste is 8.5 W/mK, and the heat conductivity of copper is 385 W/mK, or for aluminum 205 W/mK. You can see that the thermal compound is actually a poor heat conductor and that is exactly the reason why you only need a very thin layer of paste to fill the micro imperfections between the IHS and heatsink. This has always been my rule of thumb whether it's metallic or non-metallic paste. I throw on a pair of vinyl gloves, squirt a dab on the heatsink (not the CPU), and spread an even layer with my finger. I go back and fill in low spots with a smaller dab, trying for an even surface. This way, it's thin enough that it doesn't squirt out the sides when it's installed, but it's a uniform spread that covers any gaps between the heatsink and the CPU surface. Also, by putting it on the heatsink instead of the CPU, I don't risk accidentally getting paste on the non-contact parts of the CPU. I've also used the semi-solid thermal pads similar to what comes from the factory on most OEM heatsinks, but they are far less efficient than paste.