Not implemented in the bios, but still possible on OS level 
Thereâs so many threads about this exact topic, across various models with different CPU configurations, and no one else has mentioned it and/or figured it out.
It would seem you have done the impossible.
Is XD going to be your only snarky response, or do you care to enlighten the rest of us?
Tried this by unlocking all the extra âhiddenâ options for power settings in Windows 10 LTSC Enterprise. Something reverts the changes after a relatively short time span and it goes back to stock settings.
Ryzenadj lets you change the power limits and temp limits on the fly, on the intel side intel-undervolt/xtu may do the same.
Itâs an Intel system. XTU is not supported on mobile core ultra. You get an error of something like, âtried to install on unsupported hardwareâ. XTU also isnât the BIOS.
Intel Undervolt, from my understanding, works on the same premise as the Throttle Stop utility I mentioned above. Throttle Stop however doesnât allow for the usual tuning like on older hardware; those options are greyed out and not selectable. It allows for disabling boost entirely or adjustment of âSpeedshift EPPâ.
Undervolting was prevented starting with raptor lake and deployed via BIOS updates as mentioned in this Reddit article. This would make sense as to why XTU doesnât work since it is specifically mentioned. Reddit - The heart of the internet
Yeah undervolting is dead but the utility alsoallows adjusting power limits which at least up to 11th gen still worked. Somewhat unfortunate naming now.
Undervolting also retroactively got removed from a lot of coffelake platforms which was kind of a shame.
Anyway ryzenadj definitely works on the 7x40u amd framework though.
If not accessible anywhere else you could probably adjust the power limits in the ec, itâs open source and I have played with it on the amd side. I have not had a look at the intel code but it has to be done somewhere in there.
Lots changed in this regard going to 12-14th, and even more so with Core Ultra.
Iâll have to see if I can get Undervolt utility to function, but given its age..I have my doubts.
No experience meddling with embedded controller for a laptop. Pending what that entails, it may not be something Iâm willing to attempt as stability/functionality of the system are top priority and it has been functioning fine using ThrottleStop to disable boost.
It sure has
Not as much of a stability issue as it is an effort one but I can understand why you would not want to do it. Ryzenadj is much more comfortable than doing it in the ec but the scenario there was that twiddling msrs doesnât work on intel.
Throttlestop is supposed to be able to mess with power limits too so if disabling boost works that may work too. The mechanism to adjust those is the same (writing msrs).
Itâs all greyed out and doesnât function. As mentioned above only disabling boost or âSpeedshift EPPâ are available.
Speedshift EPP is supposed to be able to adjust boost frequency. How it will do so doesnât seem so obvious when looking at the software; Iâd have to take a screenshot on the laptop for further clarification. Itâs not just selecting or setting a value, or reducing current value, as functionality of the software with this newest chip is clearly limited. The way it appeared it would function was going to be more of a guessing game, i.e. test values and observe operational frequencies/power draw, and see what happens.
Guess good thing I switched from 8th gen intel directly to amd, would be infuriating not to have proper access to power limits. Used to be intel got the better toys.
A PRO variant AMD CPU w/ added security features wasnât available, otherwise I would have went with AMD.
Makes sense why your suggestions to tame this issue with Core Ultra arenât 100% relevant.
The times have certainly changed in that regard.