I have an Acer XV340CKP monitor connected via Display Port to my GPU. I also have a old LG W2253TQ that I use as a secondary display. It only has a DVI and VGA port. I have a DVI-DVI cable together with a DVI-Display Port converter to connect to my GPU, which is an Asus RX6900XT. I am running Nobara 38.
I have observed that if I were to have my Acer monitor powered when I switch on my desktop, all the monitor buttons do not respond. None of the menu buttons, not even the power button responds. When I switch off the desktop, the monitor stays on. The only way to power it down is to unplug the power cable.
However, if I were to only have the LG monitor powered when I switch on my desktop, all the buttons on the Acer monitor works.
I believe everything was working previously in Nobara 37. I think this issue probably started happening in the recent month or two.
Is this even possible, where the graphics card sends a malformed signal to the monitor and prevents the buttons from working?
Well, it's not a hardware problem in that case 😉. Good thing you fixed it 👍.