Nvidia and modesettings : second display problem

English Install/Boot/Login
#1

Hello,

I have a system with a nvidia quadro 4000 and I use the nouveau driver. Two screens (identical 1920x1080) are connected to this card:
first on the DVI output and the second on the display port (DP1) output. In KDE the screens are set as an extended screen of 3840x1080

With the xf86-video-nouveau package the two screens works but since kernel 5.13 I have flickering in some progams (Firefox, amarok, vlc)

I enabled modesettings by removing the packages xorg-x11-driver-video and xf86-video-nouveau

After reboot the two screens works: I see on both the login screen but when I log in the second screen goes black.
I have found that if I remove the ~/.local/share/kscreen directory before login that the two screens works when log in.

If I compare the Xorg.0.log and Xorg.0.log.old I don’t see meaningfull differences
Xorg.0.log where the 2 screens works: https://paste.opensuse.org/6518646
Xorg.o.log.old where screen connected to the DP1 is black:.https://paste.opensuse.org/73830484

In the /etc/X11/xorg.conf.d I have only the file 00-keyboard.conf.
in the ~/.local/share/kscreen library I have a file with this content

bash-5.1$  cd /home/philippe/.local/share/kscreen
bash-5.1$ cat 79b2453b4763624b45ca7579be82ecd2

    {
        "enabled": true,
        "id": "cfda6be1d78e8565f49a5c323fa5c3d5",
        "metadata": {
            "fullname": "xrandr-Ancor Communications Inc-VG248-F5LMQS077420",
            "name": "DVI-I-1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "overscan": 0,
        "pos": {
            "x": 0,
            "y": 0
        },
        "primary": true,
        "rgbrange": 0,
        "rotation": 1,
        "scale": 1,
        "vrrpolicy": 2
    },
    {
        "enabled": true,
        "id": "84568ff6283bf66123d8bc738b7ea483",
        "metadata": {
            "fullname": "xrandr-Ancor Communications Inc-VG248-F2LMQS017700",
            "name": "DP-1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "overscan": 0,
        "pos": {
            "x": 1920,
            "y": 0
        },
        "primary": false,
        "rgbrange": 0,
        "rotation": 1,
        "scale": 1,
        "vrrpolicy": 2
    }
]

Any hint?
Regards
Philippe

#2

Login to an IceWM session instead of Plasma. Is the behavior the same? Worse? Better? If no, then try logging out of X entirely, logging in on a vtty, and deleting all content from ~/.cache/ before trying Plasma again.

Can you reproduce using any live media’s Plasma instead of booting your installed TW?

#3

Thanks,

With IceWM the two screens are working.:slight_smile:
If I remove only the ~/.cache directory in x11 plasma then the problem remains.
When I log in without deleting the kscreen directory I have the following :

Users and input password field are displayed on both screens. When I enter the password I see on both screen the ligth bulb and below I see a cogwheel which starts to turn faster and faster and at this moment the second screen goes black. After some seconds the first screen displays the KDE desktop. In systemsettings the two screens are indentified.

I tried with a new user and on first login I have the two screens but after logout and login the second screen goes black.

I’ ll try with a live media but I must first download it

Regards
Philippe

#4

AFAIR you need to uncheck “KScreen 2” service to prevent it from loading.

#5

Hello,

In tumbleweed there seems to be no service KScreen 2. I find the next packages

# zypper se -si kscreen
Loading repository data...
Reading installed packages...

S | Name                | Type    | Version    | Arch   | Repository
--+---------------------+---------+------------+--------+----------------------
i | kscreen5            | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | kscreen5-lang       | package | 5.23.3-1.1 | noarch | Main Repository (OSS)
i | kscreen5-plasmoid   | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | kscreenlocker       | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | kscreenlocker-devel | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | kscreenlocker-lang  | package | 5.23.3-1.1 | noarch | Main Repository (OSS)
i | libKScreenLocker5   | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | libkscreen2-devel   | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)
i | libkscreen2-plugin  | package | 5.23.3-1.1 | x86_64 | Main Repository (OSS)

[FONT=verdana]But therein no service. :frowning:
Also no service in YaST.

In systemsetting there is a save choice but one of the options must be selected.https://paste.opensuse.org/97425510
https://paste.opensuse.org/97425510

Regards
Philippe
[/FONT]

#6

systemsetting > Startup and Shutdown > Background Services > Startup Services > scroll down and you’ll see Kscreen 2. Easy peasy.

#7

Many thanks,

I disabled KScreen 2 and now no more problem.:slight_smile:

Regards
Philippe

#8

Great to know! :slight_smile: