No need to OC so high. After 4.5 GHz, you are just needlessly OCing, when you won't see any benefit of doing so. 4.2 GHz on IB = 4.5 GHz on SB. For only $10 more, you can get a CPU that will bring PCIe 3.0 to the table once it is saturated. It is better than AS5, simply cuz the diff is barely noticeable and that it doesn't require 200 hrs of curing time.