There will always be a bottleneck, you can reduce it, but there always will be a bottleneck whether it be CPU, GPU, RAM, MOBO, ETC.
Personally, the only Nvidia GPUs I would buy are the gtx 970, or 980. AMD just rocks the market in terms of price/performance. an R9 280-280x can be had for about the same price, or even cheaper than gtx 960, and it will perform the same and better since it has 3gb vram, OCs very well, and the bus width it 3x larger than the 960's.