Bug 501316

Summary: 90-Hz high refresh rate no longer supported on laptop screen
Product: [Plasma] kwin Reporter: Tobiáš Potoček <tobiaspotocek>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: xaver.hugl
Priority: NOR    
Version First Reported In: git-stable-Plasma/6.3   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Display configuration

Description Tobiáš Potoček 2025-03-10 20:04:41 UTC
Created attachment 179273 [details]
Display configuration

SUMMARY
I have Lenovo Thinkpad T14s (gen 4) with AMD Ryzen 7 PRO 7840U with a 90-Hz OLED panel. Until very recently I was able to run it at 90 Hz. It was actual 90 Hz, as the screen was noticeably smoother compared to the usual 60 Hz. 

But after a recent update it's stuck at 60 Hz. There is a tooltip next to the refresh rate in Display configuration which states ""60 Hz" is the only refresh rate supported by this display". I cannot even lower the refresh rate, which I believe was before possible.

Note that this laptop was not marketed as supporting 90 Hz. Windows officially only allows 60 Hz but with some tweaks users were able to unlock 90 Hz as the hardware is clearly capable of that. Linux has supported 90 Hz out of the box.

STEPS TO REPRODUCE
1. Open Display configuration
2. Select the native resolution
3. Try to set the refresh rate to 90 Hz

OBSERVED RESULT
It is not possible.

EXPECTED RESULT
It should be possible.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora Linux 41
KDE Plasma Version: 6.3.2
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2

I'm using Wayland.
Comment 1 Zamundaaa 2025-03-10 21:21:57 UTC
Which modes are supported is decided by the display driver and not KWin, please report this at https://gitlab.freedesktop.org/drm/amd/-/issues
Comment 2 Tobiáš Potoček 2025-03-11 18:50:18 UTC
Ah, I see. Thanks for the pointers.

In case somebody comes across this, I raised it here: 
https://gitlab.freedesktop.org/drm/amd/-/issues/4038