Question questions following XTU disaster + i5 9300H safe operational limits


Oct 6, 2015
Hello there people !

I'm making this post after a rather unfortunate experience with Intel XTU and I'm very worried that I may have caused damage to my CPU. I've just got a Lenovo Y540-15IRH and since I found that undervolting is a very common and beneficial practice on such laptops I decided to give it a go.

I saw that most people used XTU so I downloaded it and immediately got to work. After a host of small (10-15mV) successive voltage offsets and stress tests from -100mV leading to -170mV, I decided to do a little research on the daunting 128A max ICC and 70W+ max sustained turbo power figures that had been bugging me from the beginning (yet since it defaulted to that, it made me think it was ok).

Based on what I found, these figures are unacceptable (even though XTU defaulted to them). I also found that XTU only supports unlocked desktop parts and some extreme edition laptop ones, so my i5 9300H is officially unsupported.

And now for the highlights of the whole disaster. In some stress tests, the TDP went well over 60W (and not momentarily), the temps capped at about 93C (where the fans went full afterburner to halt the rising inferno) and XTU's response to power/current limit changes was completely nonsensical. After applying a current limit change, it would be shown in the "Active" panel, but the laptop would NEVER boot with that limit. It ALWAYS booted with 128A as the limit (as shown in the "Boot" panel in XTU) yet displayed my setting (about 70A) as active. Regarding power, the first changes i made to PL1 and PL2 were saved and the PC booted with them, but any subsequent changes would behave like the ones made to current, with boot settings stuck to the first change. The only remotely predictable thing was voltage offset, but even that would be randomly removed from the profile out of the blue between boot cycles.

After this whole mess I downloaded AIDA64 and HWInfo 64 to see what they'd show me and the clustertruck continued. AIDA would (for the most part), show me the the PL's i configured in XTU, but HWInfo was usually stuck showing 2 specific PL1 and PL2 values I didn't input (60W for PL1 and 80W PL2) and rarely did it show the ones set in XTU. How on planet earth could these two monitoring programs disagree on ongoing PLs?!!! There even was an instance where XTU, AIDA as well as HWInfo somehow managed to display 3 different indications for the active PLs!!!

In summary, I possibly had XTU completely frick up my CPU's defaults from the get go, it responded erratically to changes in PLs and ICC, the monitoring programs I used somehow managed to disagree on the system's state and I may or may not have caused permanent damage to my device through excessive current flow and unrealistic power limits.

So, could anyone, please, tell me what the i5 9300H's safe limits are (voltages, currents, power draws)? Have I permanently damaged my device? Being the absolute dumbbell that I am, I didn't try to find out the CPU's operational parameters prior to installing XTU. I have been searching for hours and found absolutely nothing (save for the fact that I saw XTU impose the same nonsensical defaults to other 9300H equipped laptops).

Also, could someone suggest a way to fix this mess and get accurate measurements on my system's operating parameters? Resetting to factory defaults in the BIOS only results in removal of the voltage offset. No impact on ICC or PLs. Should I try using ThrottleStop?

Any advice is more than welcome! I'm devastated just thinking that I've wrecked my 750 euro laptop right after purchase!

On another note, I wish you all merry christmas and hope you have a relaxing holiday season!