Quote from Wolley74
that would also require a much more powerful PSU, he could step down to a Pentium G860 and get a bit better graphics card, but either way a new PSU would be needed for a 6770, which is pretty much bare minimum for good framerates at decent settings, a 6850 would be great, but a 6770 would also work nicely
My 500W power supply runs a 6870 and an overclocked 2500K with no issues. So I guess you don't need that much better of a PSU.
I think you should go with an H67 motherboard instead of a Z68 motherboard, it'll save you a little bit of money which you can spend on a better power supply and graphics card. Also a Core i3-2120 isn't much more than a 2100 and it'll offer just a little more performance which might be worth it in the long run.