To be honest the bottleneck in most PC's is the GPU not the CPU, I've been running a Hasswell 5820K 6 cores clocked to 4.5 per core for a while now and I have tried 3 different GPU's GTX980 , TITAN X, GTX1080TI on a ASUS IPS Gysnc 144htz 27" .
Each card is happy to run everything at 1080p at 144htz , at QHD 2560 X 1440 the 980 wont hit 144htz in modern FPS's with all the goodies but the other two are happy , and at 4K UHD the TITAN X drops sub 144 htz every now and then but the 1080 seems flawless unless you start plugging in second monitors.
4K play back/encoding the 980 is utter shit , the TITAN X is ok but the 1080 wins hands down (and the cpu or how many cores makes no difference).
Spend your cash on a good monitor and GPU , and spend what is left on a mediocre CPU ...works a treat.
Simple rules for gamers
1. always spend more on your monitor and gpu than anything else.
2. you only need SLI if you have more than one monitor or you are trying to get 2 crappy cards working which is usually pointless.
3. you don't need a 60 core x 100 ghz to run Dota2/LOL/WOW/CSGO.
4. V.R ready does require big blue or quantum computing for a 10min on rails zombie train shooter