I7 3960x Bottleneck?

When you look at benchmarks for CPU performance in games and many of the CPU's, with same GPU, show the same fps then that is an indication that the GPU has reached its limit. On the other hand when you see that you got improvement with better CPU's still using the same GPU then the CPU is the limiting factor!

pci 3.0 wont become useful until ivy bridge an no theres not a card set up you can throw at a sandy bridge that will bottleneck it

That's how I read the review. It said the i7 wasn't quite enough processing power for some of the dual and quad gpu setups in some games. It specifically mentioned it about skyrim and also said something about the software design being optimized for consoles.

From:
http://www.tomshardware.com/review [...] 123-8.html

This is because the resolution is too low for the gPUs. The GPUs are basically so powerful that that resolution relies on the CPU more than the GPU does. Not that the 3970X is weak, just that its doing most of the work at those res.

The biggest problem with three or four GPUs is that they don't scale very well. Two is pretty good these days. Near 100%. But 4 normally isn't, and for the most part you need to play at uber high res to even begin to utilize that much power.

Just to say it plainly, the i7 3K series will be more than powerful enough for probably the next 3 gens of GPUs.

Yes PCIe 3 will allow for 2x the transfer rates of PCIe 2. Just as PCie 2 is 2x that of PCIe 1. But it will probably be a few more gens of GPUs before they even begin to saturate PCIe 3 since even PCIe 2.0 x16 is not even saturated.