Herloux

Undervolting should not damage your CPU, only cause instability in high stress workloads (if not stable). But check your results with benchmarks. I've read other posts/forums where (similar to yours) Ryzen reports a high clock speed when undervolted, but performance decreases fairly dramatically (meaning 4.1@stock voltages performs a lot better than 4.1@undervolted). Not saying this is the case though, but rather be thorough.

My dear Sir... You are a Scholar and a Gentleman! Thanks!

I know you've already updated the bios, but did you check the bios setting carefully? One of my work's computer's bios has a "Upon Shutdown do..." kind of option? At one stage we also made that computer restart immediately when it shuts down.

I agree with pwn_intended. Keep MSI Afterburner open on your other screen. Detach the hardware monitor and see if your graphics card reaches its temp limit (the graph will either be at 0% at the bottom or at 100% at the top) while playing games. Also keep a look at you CPU usage and hard disk/ssd usage. Neither of them should be even close to 100% during gaming (except for possibly the loading screens). If they are, you might have another problem. Also, if I were you, I would back off a little with my overclock and test again. I really don't think its your overclock, but rather test it and be sure. Or it might simply be a Driver problem? Uninstall the drivers to your Graphics card and install the newest ones?

I'm honestly no expert. But I have received a slight shock from a speaker cable like that. Not when turning them on or off, but just when the speakers were on in general. No idea what caused it, but perhaps your previous computer was less sensitive to the issue?

It does sound like power surging back to the system. Try and reproduce the problem with other (but similar) speakers perhaps?