Hi there
I have a ROG CROSSHAIR VII HERO with an AMD 2700x and 64GB running the latest BIOS (2801), however since BIOS version 2703 if you change any settings in Fan Xpert4 or the Auto tuning the system dies and powers off, to get it running again you have to turn off the power and wait about a minute.
If you then turn on the system it restarts 2 times before POST then on the 3rd time comes up.
Every thing works fine, you can OC it to 15% and it is stable under Win 10 or Mint Linux, touch a fan (under windows) and it dies.
Needless to say I have no clue to what is happening.