Hey Scoowin,
Pairing the 950 even in SLI will be a bottleneck for that CPU. I would recommend a 970, but i get what you are going after here. I would stick with intel. They run cooler, and handle multi tasking a bit better. There are always different schools of this subject though. It seems like the 4790K will be a better buy than the 6300. Here is a link comparing the two:
http://cpuboss.com/cpus/Intel-Core-i7-4790K-vs-AMD-FX-6300
I personally like intel, and even though it looses out in core count, keep in mind the i7's have hyper threading which gives you 2 threads per core. (so 4 cores 8 threads, as opposed to 6 cores).
If you were looking to save money you could drop to the i5 or even an i3, but I assume you want to buy a good CPU and upgrade the graphics cards later down the road?
Either way hope this helps and good luck!