I guess the settings have a life of their own 
I am experiencing the opposite problem - fans spinning when they shouldn't.
Try an older driver, pre 18.12.2 and see if it helps, because this is the version that started causing my problem, so it might help you with this one.
By the way, setting you fans to 100% RPM is not necessary, unless you're running a benchmark and OCing aggressively. Even then it won't help you improve stability in most cases. Not to mention the amount of noise it will produce.
