I rarely find duals to be a good move. Most folk blow up at the need for a new big PSU or falter at the rails discussion.
We know the CPU is fine. Here's a prior quote.
"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
..
My pc specs are:
CPU intel i 5 4670 3.40 GHz.
GPU Nvidia Geforce GTX760 2gb.
RAM 8gb.
My question is should i replace the GPU to a new gtx 970 and after a year or so buy a whole new pc and add the 970 to SLI 970 or should i wait and buy a whole new pc?
And should i buy a new monitor with a refresh rate of 144hz?

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