Hello everyone,
I hope that someone will be able to help me because I am losing my nerves. I am working on F37 Silverblue + Wayland / X11. System has nVidia Optimus, with proprietary nVidia drivers (not Nouveau).
Have recently bought an external touchscreen monitor to aid my setup. The monitor nominally supports up to 1080p resolutions over HDMI or USB-C (but I don’t have a USB-C capable video output, so I have to use HDMI). The touchscreen output is sent over a USB cable, and power is received through the same cable.
Force particular (60Hz) refresh rate over HDMI
The most persistent issue I have noticed with this monitor is that it refuses to set itself at any refresh rate other than 59 or 60 Hz (although it reports that it supports up to 120 Hz – I can choose this in Gnome settings, but to no avail).
That would be fine with me except that when I try to mirror the laptop display (also 1080p), the monitor turns off and says no input device found. Now, this same issue happens when extending if I try to set it to 120 / 100 / 50 / 30 / 29 / etc. hertz.
I believe that the issue is that when I try to mirror the display, Fedora / Gnome / whomever is trying to revert back to 120 Hz for the display (because that’s what it signals it maximally supports, in theory). This makes it reject the input signal and refuse to show anything. Alternatively, Gnome might be attempting to clone the refresh rate of my integrated laptop monitor, which is, weirdly, set at 60.02 Hz, so it is above 60 Hz, so it also gets rejected.
Unfortunately, while mirroring, I can’t set a (60Hz) refresh rate – there’s no such option in Gnome settings. I can only do this if I use the external monitor to extend the display.
Another peculiar thing I noticed is that if I drop down the resolution of the external touchscreen display (say to 1440 x 900), I can now clone the display and use it as a touchscreen – but of course, the image looks horrible.
How can I go about diagnosing this, and particularly, about forcing / limiting HDMI to only output at 60 Hz regardless of what the monitor signals it supports?
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Persistent remap of touchscreen output
My second issue is with the touchscreen. It always works (sends out touch output even if the monitor itself is not displaying anything), detects multiple fingers and the like. The problem is that it somehow always gets mapped to my laptop screen. So I can touch and drag windows etc. which appear on the main laptop display blindly, but I don’t see them on the external touchscreen monitor. And windows that appear on the external touchscreen display are not affected by touch (i.e. because it is mapped on the main display).
Regardless of where I put the external touchscreen monitor in Gnome settings (left, right, above, below the laptop screen), or whether I select it as the primary or secondary monitor, the touchscreen output is persistently mapped to the laptop monitor. Only if I turn off the laptop monitor the image gets displayed solely on the external touchscreen monitor, only then I can use it as a touch device – but then I have one display unused for anything.
And of course, if I lower the resolution I can clone the display, and then the touch output corresponds to what is displayed on screen – but it looks horrible.
I guess the question is: how can I consistently remap the touchscreen to the appropriate monitor?
I prefer to work on these problems through Wayland, but X11 would be the second-best alternative. Is there a GUI tool to work with these kinds of issues? I’m still a newbie.