The original Precision Boost Overdrive enabled Ryzen CPUs to meet increased performance demands by dynamically increasing clock speed and power draw from the motherboard. The system is considered safe enough that AMD is happy to put it out there, although as this video about it from 2018 reminds us, it was still considered a significant enough variance from factory settings to void your warranty.
The big step up with the newest version of Precision Boost Overdrive is an automated overclocking feature to further increase the boost clock by as much as 200MHz. In the example given in the video, AMD's Robert Hallock talks about taking a 4.55GHz boost speed to 4.75GHz. Boosts on top of boosts within boosts. A boostception.