Originally Posted by Captain Dan
Anything below 60°C is good (But not too low)
It's hard to go too low on a CPU, and 60 is nowhere near that threshold. For extreme overclocking, CPUs are often put under liquid nitrogen. My quad core idles at about 32-35C and never loads above 55C. CPUs love being cool.
Originally Posted by Raybo
I ain't buying the 11 degree better performance from different thermal paste, something else had to be amiss for that kind of drop.
You're correct. Most commonly, too much thermal paste is used. The factory paste usually comes in pad form, and on older CPUs is a tad too much for optimal heat transfer. It's really only meant to fill microscopic cracks and slight inconsistencies in the shape of the heatsink and CPU. Metal on metal gives better transfer.
Also, the best application method is different depending on your type of CPU, but you never want to use any more than about 3/4 the volume of a green pea. You usually don't want to pre-spread it either, the pressure from the heatsink will spread it to where it needs to go.
That being said, Arctic Silver is one of the most commonly used thermal compounds in the PC enthusiast community