Hey all,

My laptop (Asus RoG Strix 16 G614 from 2024) is connected to an external monitor via HDMI (Gigabyte M32U - 4k, refresh 144 Hz).

On the built-in display (240 Hz refresh rate) everything works smoothly. On the external monitor under Wayland, some games report frame rates around 70-80 fps (game internal indication), but the real experience is more like 10 fps. When I move the mouse cursor slowly, it visibly skips, while it’s completely smooth on the built-in display.

When I change Wayland to X11, all is well, and the experience matches reported frame rates on both monitors.

I see two similar threads have not resulted in any resolution so far:

• Games Visually Stuck at Low Refresh Rate on 240Hz External Monitor (Wayland + NVIDIA Hybrid GPU) - #2 by kanexiik
• External monitor with Nvidia eGPU unusable with Wayland, works on X11

Is there any resolution so I can use Wayland again? If not, is there a bug I could contribute my findings to?

Thanks all!

Hi I’m the OP from the first thread you linked.

Some clarifications: in my particular setup, the most likely culprit was the eGPU factor. First of all, my card in that example was old enough that Nvidia dropped support for it and I had to install custom drivers prepared by the Arch community. I experimented a lot, but while it’s true that switching to X11 and capping display at 120Hz helped as a compromise, the main problem was the niche hardware setup.

Prior to using that exotic setup, I had a functional Asus rog with an RTX 2060 (GA401IV), and Wayland posed no issues with Cachy or even Nobara. Unfortunately that computer died and I had to switch and get creative.

Now I’ve rebuilt a desktop PC with an RTX 3060. Strangely enough, I did get a modest number of green dot flashes on Wayland (sort of a precursor to screen tearing) with HDMI, but everything went away when I switched to display port and forced 144Hz (S2127DGF, 1440p at 144Hz max) Unfortunately I did not experiment much so this example might not help a lot in diagnosing your problem.

Given that you are having problems despite having a far more capable system than mine, and that the mouse skipping outside of the game hints at screen-tearing, I suggest first capping at 120Hz on HDMI in settings and disabling any freesync or analogous feature on your monitor’s menu, then if it doesn’t work trying a different HDMI cable and ultimately a displayport cable (they’re not that expensive). If DP doesn’t work, cap it at 120Hz or even lower, the idea being to isolate under which conditions the screen tearing occurs.

From my research on the problem, there was a known bug Low fps on external monitor connected to nvidia hdmi port · Issue #650 · NVIDIA/open-gpu-kernel-modules · GitHub that leads to framerates being halved (roughly corresponds to your 70-80 vs 144 figure). If you switch to 120Hz now and it drops to 60 it will be a solid hint

I’m trying to recall from imprecise research memories here, but I also remember reading that users had some measure of success with bad KDE/Nvidia situations by disabling the iGPU in BIOS, switching drivers and removing GSP firmware (IIRC open drivers can’t do that by definition, but it might have changed in the meantime), experimenting with locking gpu clocks with nvidia-smi
Perhaps you could try checking if the GPU is kept at a low p value with watch nvidia-smi command if it’s not between p0 p2 might be that it is not correctly prioritized. To force prioritize you have to edit the env file with a specifc Kwin command but I don’t recall how it works.

EDIT: I left it after my ROG died but there is a discord server dedicated to linux rog issues so you could try asking there as well