Cause the CPU can get unstable under certain loads. So Intel plays it safe and ramps up the voltage.
And no.. there is no easy way to measure this. Also every CPU is slightly different.
I ultimately gave up playing this game, spent hours testing and tuning. Each core is slightly different (on amd, I’m sure intel has something similar) and stress test for 1-24h each tweak invoking a reboot. Then some new workload comes and kernel panic/bsod.
Stock settings just work, maybe I lost the silicon lottery but too tired to check anymore.
It's not just unstable, it's a security issue because control over CPU voltage allows someone to use that instability to compromise computations that are supposed to be performed securely (e.g. look up "Plundervolt").
If plundervolt is a viable attack you’ve got much bigger problems (the attacker must already have gained full privileges). Not sure how this is relevant to just using throttled or similar to conditionally undervolt the CPU with fixed levels that can be proven reasonably stable.
Stock settings just work, maybe I lost the silicon lottery but too tired to check anymore.