I have a gigabyte gtx 1080 extreme gaming and noticed many bugs with various version of extreme engine:
the pc reboot or restart does not keep saved the custom curvature of the fan (manual setting)
with all profiles (2,3,4, +) created to oc you do not want to set the fan to 100% but only with the profile 1 can send the fan to 100%.
I hope that these measures are useful for developing better software