That CPU is more than enough. In fact there isn't a single GPU out there that may get bottlenecked by your CPU. I'd suggest you get the 6GB version. It may be more expensive but it's also faster and more future proof since it has more memory. Nowadays 3-4GB of GPU memory is considered the minimum but in a year or two it won't. It also depends on the resolution you are planning on gaming, 3GB of memory is enough for 1080p only. Higher resolutions demand more GPU RAM.