the built in display works as it should at 1080p 144hz games are flawless aswell as all other uses, i have a new monitor that is 3440x1440 165Hz its plugged in by a amazon basics hmdi which probably only supports 100hz which is my only option when changing refresh rate. 100HZ feels like 60HZ and i have been scrolling the web looking for a fix and have not been successful.
system says display driver is the most recent and i have nobara 39 newest update.
hey man, I’m in the same situation as you. My new 100hz ultrawide is apparently running at 100hz but to me it looks like 60hz. May I ask if you found a fix? the monitor I’m using is the samsung LS34C500GAUXXU .
i had a similar issue. laptop with integrated amd graphics and discrete nvidia gpu.
for my external monitor i could select 144hz, but everything was very laggy. laptop internal screen was smooth as butter. didnt matter if i connected external screen to hdmi or displayport over usb-c.
had the issue on multiple linux distributions (ubuntu, fedora, opensuse), both KDE and gnome desktops, and for nvidia drivers 535 and 545.
no issues at all in windows 10.
turns out that on my laptop, external monitors always connect directly to the nvidia gpu even if i run hybrid graphics (integrated and discrete graphics both active).
linux drivers and/or kernel can’t handle this well it seems.
solution that worked for me was to disable the integrated amd graphics in BIOS/UEFI settings (i believe it is sometimes called a MUX switch).
a bit unfortunate, as i would prefer to run the monitors with the integrated amd graphics, and have as much gpu memory as possible available on the nvidia card for cuda stuff. laptop fans also spin up more often now, presumably due to nvidia card not being as energy efficient as integrated amd graphics.
edit: oh, and i should mention that during my troubleshooting i also found out that there are some licensing issues with hdmi in linux, in particular with hdmi version >2. i’ve seen claims that nvidia and intel proprietary drivers do have support, but in general it seems using displayport for your external monitor is a safer bet for high resolutions and refresh rates.
Heres the bug report. my monitor is supposed to be 165hz i can only achieve 100hz on nobara and it feels like 60hz it will operate at 100hz on windows but its supposed to be 165hz im not sure what the deal is.
Did you see the reply above…it’s probably defaulting to reverse prime, e.g. rendering on the iGPU, copying the framebuffer to the dGPU, which sends it out to the display.
If the iGPU is only refreshing at say, 60Hz, it won’t matter that your monitor is supposed to be 165 or 144Hz or whatever, the image itself will only change no faster than the 60Hz iGPU.