I have an i7 4770K @ 3.5 stock cool. I want to OC over 4.0, 4.5 maybe? 4.7? not sure which is best. What exactly would I need to OC it? A cooler? anything else? would i need more power? i have a 600W and I think all slots are taken. Also what kind of cooler would be best and price doesn't matter.