Originally Posted by AlDyer
Afaik the scaling has lowered on earlier processes too. You have to scale the inreases to the original clocks. Also that "only thing" happens to be propably 99% of the users. I'm not saying they are bad chips, I just wouldn't be too excited about the performance increases of Broadwell. Intel seems to be going towards the lower power consumption direction.
The extra potential of the chips (percentage over stock speeds) hasn't really gone down overall. It has actually stayed at relatively the same levels with SB providing a small higher than normal moment.
Yes the potential might be down from something like a 2.66ghz i7 920 D0 but this is because the 920 was pretty much the bottom bin nehalem quad.
Let's compare the highest clocked intel chips of every recent series:
process - CPU - stock speed - average max OC - OC potential in percentages
45nm - i7 965 C0 - 3.2GHz - 3.8GHz - 19%
45nm - i7 975 D0 - 3.3GHz - 4.2GHz - 27%
32nm - i7 990X - 3.46GHz - 4.4GHz - 27%
32nm - i7 2700K - 3.5GHz - 5.0GHz - 43%
32nm - i7 3970X - 3.5GHz - 5.0GHz - 43%
22nm - i7 3770K - 3.5GHz - 4.8GHz - 37%
22nm - i7 4770K - 3.5GHz - 4.7GHz - 34%
22nm - i7 4960X - 3.6GHz - 4.7GHz - 30%
Core 2 had a crapton of extreme models which I can't be bothered to list but it should also fit pretty nicely in that trend. SB was exceptional for air/water users. Otherwise different intel process nodes have always had their own characteristics when it comes to OCing. And I haven't seen any proof of a general downwards trend.