"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
So an i5 is not a bottleneck for THREE cards, Your setup is a single card.
Bob
My current system:
_CPU AMD FX-4300 Quad-Core 3.8GHz (I overclocked it to 4.5GHz)
_GPU Nvidia Geforce GTX 550 Ti 1GB
_RAM 8GB
_PSU EVGA 600W (Bronze)
I'm planning on upgrade my GPU to the EVGA GTX 760 2GB. Will my current CPU (with a overclocked 4.5GHz) bottleneck this card? If it will bottleneck, about how much is the bottleneck? Thank you.

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