the cpu is way over kill. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
give you the same bang for the buck with the 670 video card. most games right now dont use more then two cores of a cpu.
the ib i7 4 core not going to bottleneck the 670 if you match it up to a good gaming mb like a asus sabertooth or other good 16/8x8/ pci 3.0 mb. your better off using that saved cash for a better gaming case that has better air flow and wire management.
For just gaming? No. That processor is 3 generations old and while still very powerful for things like video encoding and rendering is not what you should get for a gaming computer. In most cases games do not use more than 2 cores although some few can use quads. I do not believe a single game will make use of 6 cores.
For gaming get an i5 2500K or i5 3750K with a Z77 motherboard. If you truly think you need a 6 core CPU at least get a current generation LGA 2011 setup with an i7 3930K.
Everything else looks pretty good. You might want to look into a little better case. Nothing wrong with an Antec 300 but with a higher end gaming system you would do better with an Antec 900/1100/1200.