I had one for the earlier Polaris cards but its different now on RDNA cards.
However, its still easy and other than stability issues, crashing, reboots and BSODs, no harm can be done. Be sure to stress test your undervolt settings to ensure stability.
To start, use the option auto undervolting to have a value to start with. Then go to the manual slider and lower it a bit more. Increase power limit and check temperatures and stability.
I'll try to post some pictures when I'm home.
If the temperatures please you, maybe you can now overclock a bit to get more.
To give you and example, on my old Polaris card, I had it undervolted and overclocked for several years with no problems whatsoever.
Good luck
The Englishman