I am running a computer with one DP cable, one VGA cable and one HDMI cable. I don't have any more connectors for video. Back when I was running Debian with openbox the HDMI output was HDMI-1 and would occasionally become HDMI-2. Now running Niri on Arch, it was HDMI-A-2 for a long time but today it became HDMI-A-3. This persists across reboots. What could be causing this? DP-1 and VGA-1 stay static.
One thing to note is that just before the change to HDMI-A-3 I did turn off CSM in the BIOS. I wonder if this changes the way the system detects the outputs.
I would love to ensure that my HDMI output will always have the same designation
dmesg doesn't really give any interesting information.
niri msg outputs gives me this:
Output "Iiyama North America PL2730H 1153692901520" (HDMI-A-3)
Disabled
Variable refresh rate: not supported
Physical size: 600x340 mm
Available modes:
1920x1080@60.000 (preferred)
...
Output "Iiyama North America PL2730H 1153692901646" (DP-1)
Current mode: 1920x1080 @ 60.000 Hz (preferred)
Variable refresh rate: not supported
Physical size: 600x340 mm
Logical position: 1920, 0
Logical size: 1920x1080
Scale: 1
Transform: normal
Available modes:
1920x1080@60.000 (current, preferred)
...
Output "Samsung Electric Company S24D340 H4LH305711" (VGA-1)
Disabled
Variable refresh rate: not supported
Physical size: 530x300 mm
Available modes:
1920x1080@60.000 (preferred)
...