Arch Linux

AlexRaw

Member

Registered: 2019-10-04

Posts: 2

Last monitor that is plugged in is not detected

Hi,

I have a weird issue with my monitor setup. I have three monitors, 2 through HDMI and one through DVI with HDMI to DVI adapter on a Radeon RX 580. It has been working just fine for a long while until today. I woke up my system from sleep, and the third monitor stopped showing a signal. There was no reboot nor update. This has happened once before, and I don't know what fixed it. I just plugged in and out cables and rebooted; it just showed up again as spontaneously as it disappeared.

On boot, all monitors work fine in grub. After that, I lose the signal of one of them.

The monitor says, "no signal detected".
Xrandr says, "disconnected" for at least one of the monitors.
I have changed the cables around in all permutations and it doesn't seem to be the adapter nor the cables nor the monitors. Whatever monitor is plugged in last doesn't show up independent on the cable or input.

$ uname -a
Linux rawpower 5.7.2-zen1-1-zen #1 ZEN SMP PREEMPT Wed, 10 Jun 2020 20:36:27 +0000 x86_64 GNU/Linux

I've tried booting in the lts-kernel, same problem

$ pacman -Q | grep amd   
amd-ucode 20200519.8ba6fa6-1
xf86-video-amdgpu 19.1.0-2

I thought it was a flimsy cable, but the fact that it works in grub, and that some constellations work just fine leaves me clueless.
I'd really appreciate some help on where I could start troubleshooting.

I thought to try using one of the spare display port inputs on the graphics card instead. But before I buy another cable or adapter, I wanted to make sure, there isn't a software issue.

Extrasklep

Member

Registered: 2020-01-08

Posts: 3

Re: Last monitor that is plugged in is not detected

I have a similar problem on my rx 550, my second monitor connected to DVI doesn't get detected no matter what but it works just fine in the bios until the linux system loads the gpu drivers
The main HDMI monitor connected through a DVI to HDMI dongle to that DVI port can get detected somehow but not the second monitor
Yesterday I fixed it by changing some display init setting in the bios but today I resumed my computer from hibernation and it's broken again even after rebooting, and messing with that bios setting again does nothing anymore...