Currently got an E6420 running at 3ghz, and have the option of putting my 6420 in another machine and going for a new CPU. The Q6600 looks like the most worthwhile upgrade without spending silly money, but will I get much more out of it, considering I don't do any video encoding (I will be playing a fair amount of games though). Is the cheapest yorkfield quad much more of an upgrade from the Q6600, as I've heard they don't clock as well?Thanks