Windows 11 on Helios 500 Laptop - CPU Power Throttling, Cannot Undervolt

AlexE
AlexE Member Posts: 41 Devotee WiFi Icon
edited October 2021 in Predator Laptops
Hi, an observation/warning rather than question - though any tips appreciated.

I recently 'upgraded' to Windows 11 on my Acer Predator Helios 500 laptop (i7-8750H & GTX 1070).  It looks nice, but I noticed games FPS was a little lower and would also 'dive' so that whereas on Windows 10 games like Fortnite could be a stable 144 FPS on some settings, and 'light' games like League of Legends would easily run at 144 FPS.  Now on Windows 11 they would show FPS ranges of 70-144 FPS, varying by the second - but often keeping the maximum of the range at 144 FPS.

Looking at Intel XTU, I could see the CPU was Power Throttling even when set to 'Max' in PredatorSense - even when the laptop is just idling!  Under Windows 10, it would rarely throttle even in Fortnite when set to 'Max'.  I checked in HWInfo that the TDP was being set correctly by PredatorSense, and it seemed to be.

However, I then noticed that the Voltage Offset was 0.  I believe Acer themselves have been undervolting these laptops by 125mV at least, possibly set by PredatorSense itself.  I tried to undervolt using ThrottleStop and no matter what I couldn't change the undervolt from 0mV.  This is probably a significant part of why the laptop is power throttling.

I will therefore be going back to Windows 10 until you can undervolt as normal again.  Edited to add - I checked, and this laptop does not have the Core Isolation / Memory Integrity enabled - so that's not the problem.

Below is Intel XTU showing CPU Power Throttling, while laptop is idle.  100% throttling is when PredatorSense CPU Power Limit is 'Normal', and oscillating is 'Max'.


Below shows ThrottleStop trying to set the undervolt and HWInfo Sensor Status - both refusing to change the undervolt values, after being applied.


Best Answer

  • AlexE
    AlexE Member Posts: 41 Devotee WiFi Icon
    Answer ✓
    Update: It seems VBS "Virtualisation Based Security" was running on my laptop after upgrading to Windows 11.

    I thought 'Core Isolation' turned off already disabled it, but seems it was still enabled as seen in "System Information".

    This excellent guide showed how to properly disabled VBS - https://nerdschalk.com/how-to-disable-vbs-on-windows-11-and-does-it-help/

    After disabling in BIOS, the VBS was finally disabled.  Undervolting works again, showing the default -125mV and the laptop is running with a lot less CPU Power Throttling - though still a bit more than Windows 10.  The laptop feels more responsive!

    I've not tried gaming yet, but am optimistic this will be better - perhaps Windows 10 levels.

    A little disappointing as I'd like to use WSL 2 which required virtualisation enabled, but I will make do.  Hopefully WSL 1 still works.

Answers

  • AlexE
    AlexE Member Posts: 41 Devotee WiFi Icon
    Answer ✓
    Update: It seems VBS "Virtualisation Based Security" was running on my laptop after upgrading to Windows 11.

    I thought 'Core Isolation' turned off already disabled it, but seems it was still enabled as seen in "System Information".

    This excellent guide showed how to properly disabled VBS - https://nerdschalk.com/how-to-disable-vbs-on-windows-11-and-does-it-help/

    After disabling in BIOS, the VBS was finally disabled.  Undervolting works again, showing the default -125mV and the laptop is running with a lot less CPU Power Throttling - though still a bit more than Windows 10.  The laptop feels more responsive!

    I've not tried gaming yet, but am optimistic this will be better - perhaps Windows 10 levels.

    A little disappointing as I'd like to use WSL 2 which required virtualisation enabled, but I will make do.  Hopefully WSL 1 still works.