Zenbook UX325EA weird thottle coming back to and from AC mode

[gabrio81]

System: Windows 10 Home
Battery or AC: both
Model: UX325EA
Frequency of occurrence: always
Reset OS:
Screenshot or video:
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Detailed description：
hello,
When i start my laptop the CPU is 90% of the time at a nice high speed on OC and super stable, whether it's on AC or also on battery - in high performance mode, and "performance" from the Asus app, great!! for instance i get 4.05 - 4.35 - 4.50 ghz.
BUT when i unplug AC then it drops down noticeably. Even if i am on battery FIRST stable on 4.3ghz then I plug in the AC then it drops. it seems when there is a "change" in power source, there is a drop or something triggers.
Why does this happen?
During these times, laptop wasn't under pressure or load or anything at that time, so is really cold and cool, no temperature increase (which i know affects the tiny zenbook), so why does the clock drops so much when you change the power source? either on battery TO AC or AC to battery? simply by unplugging or plugging it? all intel power savings are switched off.
is that because the machine thinks that during AC operation it might overheat? then if i restart it goes again to high frequency. or just cycling on and off hibernate 2-3 times, which is what i do most often, sometimes it even takes 4 cycles of hibernation, which are fast anyway since it's a very fast laptop. Still is it possible to avoid this?
thanks
Gabrio

[gabrio81]

I actually did a test with UserBenchMark.exe and i got for desktop i think 96% or 98% and "Nuclear Submarine" with my extra coolpad which is pretty amazing.
This time i didn't force the 4.xx Ghz mode, i plugged back AC and let it do its thing. Didn't affect a performance test in the end. Which tells me it's probably fine either way. (it would bump up CPU speed on need, just not keeping it high all the time when not needed, which probably is also smart to do).
Gabrio

[Blake_ASUS]

Hello Gabrio,
Can you enter BIOS and load default setting again?
And can you try safe mode? to see if there is the same issue.
Thank you.

[gabrio81]

i've already loaded BIOS default settings as asus tech support suggested me as well - no change.
I have also restarted in Safe Mode and interestingly the CPU speed is locked to non-turbo values that way, doesn't matter what you do, i tested a speed test and wouldn't go higher than 2.80 Ghz. So in Safe Mode the CPU doesn't grow but it's fixed at 2.80 Ghz.
I also had 2 "high performance" power mode so i deleted one to remove duplicates now they are all unique.
still, no change.
thanks,
Gabrio

[Blake_ASUS]

Hello Gabrio,
I'm thinking that we need to try reset.
Windows 10 - How to restore the system to factory default settings? | Official Support | ASUS GlobalLet's run only the Windows update after the reset. And see if you still have the same issue.
Thank you.

[gabrio81]

hello, that's gonna be difficult as this is my work computer.
Do you have another Zenbook where you can test this? before i go ahead with any resets.
Bear in mind i disabled modern standby because i want to have the regular power plans.
This machine by factory has modern standby which means you don't have High Performance, Balanced, and Power Saved by default and i was told by Asus support that it's the "recommended". So at one point they told me i am running an unsupported setup, that to me is nonsense.
However - it could be why the CPU is having this behaviour.
So if you have a Zenbook from head office to try on, could you ask if it makes this behaviour too?
thanks,
Gabrio