I'm sure you've read something like this.

"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-4.html

It looks like a game machine so why not a cheaper quad core or i5 as noted and a better GPU from the next link?
http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107.html

Bob