Now I did find "Peripherals" > "AMD CBS" > "Zen Common Options" > "Custom Pstates/Throttling"
At that point you get a full screen, screaming announcement of death and destruction for your cpu
I'm down to 1.21 volt on the cpu @3.9Ghz and I'm going to stay there for a while.
There maybe more downward room in the voltage. Have not crashed with that yet.
With speed ... 3.925Ghz works 3.950 crashes. Think I'm good for now.
Oh... those dynamic Vcore options were "grayed out", not functional.