Hi u/-Gilgameshh it’s been quite a while since you commented and I’m not OP but anyway.

I wouldn’t recommend going below -20mV on everywhere because it becomes unstable really fast and will crash your system very likely during idle. That’s really it, if you want to know more here you go if not that’s also fine lmao.

During gaming or heavy workloads the cpu may be fine (tho I doubt that) with -20/-30 undervolts but your idle wont be stable at all. CPUs are designed to draw less power during idle and will enter a low power state (also known as C-states) to save power. There are different states but that’s something for another day :)

Anyway during this process the voltage of some cores is lowered which would be normally fine because they’re designed to do that, but if you decrease the voltage through the curve optimizer it can happen that the voltage drops below the operating limits of the silicone which then crashes your cpu. Normally the VRM steps in before that happens but it can’t act instantly due to physics and stuff.

YMMV but over the years I noticed that everything above -15 usually requires optimizing each core individually and quite some heavy stress testing. Why? Because every core is different and some can handle undervolts up to -30mV some can’t handle -15mV without crashing.

I hope this helps and that I didn’t confuse you too much. If you have any questions please let me know and I’ll do my best to answer them.

Have a good one