This is NOT undervolting per-se, we just decreasing voltage to cpu and cpu soc and pbo/boosting disabled, for now.
I think the range 1v - 1.2v should be enough.
Anything above 1.35v that's too much and not worth it imo.
I think 1.1v constant on CPU and CPU-SOC should be enough.
If it fails to boot in windows with that voltage welp bios/CMOS reset back to bios disable fast/quick boot and change voltages to 1.2v
( Yes, a game of bit trial n error but that's only if it fails to boot into windows )
There are certain voltages below which it might not even boot into windows.
Remember there is also ram soc voltage don't touch it thinking it's cpu -soc voltage.
( I dropped 10C just when I turned down voltage from 1.3-1.35v to 1.175-1.25....
Though Further decrease in voltage didn't drop temp as much.
Right now I am using it at 0.8-0.85v cuz I don't use pc for gaming right now and it's a am5 cpu btw, so your mileage may vary. )
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You haven't answered yet,
You got any thermal paste?
Which one is it?
Did u by any chance saw which thermal paste did they use?