Don't forget that every chip is different. You can take two Ryzen chips off the shelf and have one be happy at 4.0 GHz and the other unstable at 3.8 GHz. That's the silicon lottery.
I always start at the base frequency and base voltage and go up 100 MHz at a time until the system gets unstable. Then I start increasing the voltage, incrementally and slowly.
I overclocked my Ryzen 7 1700 from 3.0 GHz to 3.6 GHz and only had to increase the voltage to 1.2V.