I'd have to say yes, overclocked CPUs run hotter. As fot eh Sk-6 helping, what HSf do you have now? If you have a FOp38 or somethig similar, a Sk-6 wont make that much of a difference, but chances are it would get it to well below 45. I had a FOP32-1, and my CPU was often around 50 C (1GHz Tbird @ 1.3) with an Sk-6 + delta 60mm, it is now around 38-42 or so.