Here's my take on coolers. A lot will depend on your ambient temps. If your computer is in a very cool room, it will perform better. For an air cooler to cool something like a 3770K @ 4.8 running Prime95 for 12 hours, it had better have a very large surface area and be in a very cool room. I don't live in a cool climate and I have a Noctua NH-D14. It does not block any ram slots if you install it correctly. It has a 44mm clearance for ram. G Skill ripjaws is 40mm tall, like most ram without the large heat spreaders. The Noctua will not cool the 3770K at those speeds running Prime unless you have extremely low ambient temps. The next step up is water cooling. In a warm climate, even water cooling will be challenged, but can do it. If you search the internet, you will find complaints of heat with most of the Ivy Bridge CPUs. They will run at normal usage fine, but running a stress program like Prime, IBT or AIDA will produce exceptionally high temps. The end result, is water is better at cooling than air. But, it is a fact with either one that low ambient temps and surface area are required for high end cooling. Even water cooling, that is the reason for the large radiators, more surface area to remove the heat.