I've searched the net far and wide about this question, and no one seems to have a legitimate answer. The question is this, "what is the danger of applying to much/little thermal compound?" I have i7 quad and using IC Diamonds, I've applied about a grain of rice size on all four corners and one in the middle and then put my heat sync back on. Is that the correct amount?
IC Diamond is a very thick thermal compound there are specific application instructions
for it, and you will not achieve maximum results from it's capability if you don't follow their tested application method.
It also operates best under a 50psi clamping pressure.
And to answer your question too much thermal compound acts as an insulator instead of a conductor of the heat.