I think this is bottlenecked



There is nothing at all wrong with that build. There is but one thing that I would change, however. You have a pretty high end system with great components, but choose at least 1866Mhz RAM instead of 1600Mhz. You can even jump to 2133Mhz if your wallet can handle it. Your choice of RAM type and brand couldn't have been better, but you will benefit from the extra speed of frequency.