I run the H100i V2, 2700x on a ROG Crosshair VII Hero and set it to level 2, PBO, XFR etc on. Also set my ram profile up correctly too.
it weirdly hits boosts of around 5.9ghz sometimes in HW Monitor - guessing that's a data reading glitch?
Anyways, temperatures don't really go far over 60 celcius under stress, depending on the voltage it's putting out.
Highest I've seen is 69 at 100% 4.3ghz boost 1.45v that was sustained for a while. The minute I took the load off, it was back down to high 30's (celcius)