What cpuz reads should be your actual vcore, will read lower than what you set in bios due to vrop/vdroop unless you enable LLC. I wouldn't use auto settings for vtt, the board will probably over volt it. It seems 1.21vtt is what Intel says is the max safe, that will limit overclocking a bit.

I was able to get 4300mhz to run 7 passes of linx but after that i get errors, using 1.45 vcore load, 1.4vtt and 1.175pch, temps were ok but had heavy ac on the rad.