I'm putting a PC together for the first time and for the CPU I bought a retail AMD 64 3200+. I was looking over the heatsink fan combo that came with it an there appeared to be a pad of something on the bottom of the heatsink. Is this some kind of thermal compound? If so would I be better wiping it off and using something like Dynex instead as a thermal compound? Or is it just some kind of protective pad to keep any dust from collecting on it during storage/shipping?