Well the 3570k is the new generation, if theres not much of a price difference you will get more of a benefit from that. Uses newer technologies etc. Both are unlocked for overclocking, but i think serious overclockers will say to stick with the 2nd gen chips, as they use less heat. If your just doing a mild one then go with the 3570k, its pretty much as good as you can get for gaming. Whats your budget and requirements on a motherboard?