Locked out of monitor after setting "bad" resolution

English Install/Boot/Login
1

I have been running Leap 15.6 for months. I began using Wine and managed to get Quicken 2002 working, but the fonts were tiny. Flushed with success, I used System Settings/Display Configuration to change the resolution from the default 1920x1200 to something a lot lower with the same aspect ratio. (I can’t remember exactly what I chose, unfortunately). Immediately I applied, the monitor displayed a pop-up saying “Current input timing is not supported by the monitor display…”

The monitor is shared through a KVM switch with another computer, and it works perfectly when switched to that one. But nothing I can do changes that message on the first PC. It’s not a hardware problem; I somehow managed to tell Leap to use an incorrect value which it always sends to the monitor. I can boot OK, up to the point where the welcome screen appears - and then the monitor puts up its message.

I don’t think the hardware is relevant, but it’s a Ryzen 5 1500X with 16GB RAM. The graphics card is an ATI Radeon HD 65xx (ancient but adequate for my purposes). The monitor is a Dell U2412M.

What I think I need is to edit some file(s) after booting nomodeset, to set the monitor to the proper resolution 1920x1200-60. But that’s definitely beyond my competence.

2

Which DE are you using? Welcome to what? Are you able to login, and only after that the error occurs? If you are able to login first, then the trouble is near certainly something saved to ~/.config/ somewhere. Are you able to Ctrl-Alt-F3 to reach a shell prompt? If yes, a new user can be created (using either text mode YaST, or useradd command), to use to attempt to login normally, proving problem is a saved personal setting. You could zypper install mc (if not already installed), then use mc to navigate your ~/.config/, search for something setting a mode that is not 1920x1200, then delete it or change it to 1920x1200. While searching ~/.config/ mode, also you could empty ~/.cache/, which could possibly hold the deviant setting. There’s zero harm in emptying ~/.cache/ as programs know how to fill it right back up as needed.

2 Likes
3

Thanks for your prompt and helpful reply, mrmazda!

Which DE are you using?

KDE.

Welcome to what?

The KDE “Welcome” window that appears after login, offering all sorts of help.

Are you able to login, and only after that the error occurs?

Unfortunately not. I am the only user on my home PC, and I have login disabled. If I accept the default boot, I see the light bulb logo for a while, then it disappears and I see the Welcome window for a moment; then the monitor puts up the timing window and I can no longer use it. If I boot with nomodeset I can use the monitor but I am stuck with a low resolution for the rest of the session.

So I guess I am being silently logged in, or I wouldn’t see the Welcome window. Seconds after, the monitor is disabled.

Thanks for your suggestions; I’ll try them and post the results.

4

Hi, what about backup and then delete the ~/.local/share/kscreendirectory contents, (while not logged in)? I found this :< [SOLVED] Is there any way to reset monitor configuration? - Help - KDE Discuss

The user claims the following :< I have noticed this directory no longer exists on KDE Plasma 6

I am using KDE Plasma Version: 6.5.2with a single screen and do see the directory on the machine here.

# pwd
/home/username/.local/share/kscreen

Which includes the following contents:

# ls -lah
total 12K
drwxr-x---.  3 username username  101 Feb  6  2025 .
drwx------. 53 username username 4.0K Nov 15 01:10 ..
drwxr-x---.  2 username username   86 Feb  6  2025 outputs
-rw-r-----.  1 username username 1.2K Feb  6  2025 c0414949b26e2ab93769802332f033a7
-rw-r-----.  1 usernaem username  567 Nov  4 17:41 f38c99a3b72d1a4e923ba7b9682bc8e0
HP-Pavilion-g6:/home/username/.local/share/kscreen #
1 Like
5

In .config/session there is a recently modified file called kwin_saved at previous logout. It contains the following lines:

geometry1=0,0,1400,1050
geometry2=0,1006,1400,44
geometry3=0,1006,1400,44
geometry4=0,0,1920,1200
geometry5=448,160,1024,844

The correct setting for my monitor is 1920x1200-60 which is similar to geometry4. And System Setting/Display Configuration shows 1400x1050 as the default and only option - imposed by nomodeset.

If my wildass guess is right, I could somehow edit those lines and fix the problem. But I am belatedly developing respect for the ease with which I can screw things up.

Any suggestions?

6

See my post above. On a second thought you may be onto something. You could try renaming kwin_saved. I do not see that file on the laptop here JFYI.

1 Like
7

I found a file in .local/share/kscreen/ that looks promising:

[
{
“enabled”: true,
“id”: “d0e3c5ebc4b149fa4725cae39ed8c5df”,
“metadata”: {
“fullname”: “xrandr-Dell Inc.-DELL U2412M-30WJ1634004L”,
“name”: “DVI-D-1”
},
“mode”: {
“refresh”: 59.98658752441406,
“size”: {
“height”: 800,
“width”: 1280
}
},
“overscan”: 0,
“pos”: {
“x”: 0,
“y”: 0
},
“priority”: 1,
“rgbrange”: 0,
“rotation”: 1,
“scale”: 1,
“vrrpolicy”: 2
}
]

8

That does look like the one to delete, though as 1280x800 is the same aspect ratio as 1920x1200, it’s a bit surprising that the display wouldn’t accommodate it. I’m sure it was not there the first time you logged in, so it should be perfectly disposable. That said, you may need to be in logged into a non-Plasma session for deletion to stick. If it does not, try logging out of plasma while booted in nomodeset, then logging in on a vtty (e.g. Ctrl-Alt-F4) to rm it before rebooting without nomodeset. If it still doesn’t work, I’d also delete the file with the geometry lines, which again, would not have been there when opening Plasma for the first time.

1 Like
9

Yes, remove it and kwin will regenerate it when logged back in.

2 Likes
10

I am pleased to say that panorain’s original suggestion fixed my problem. I had tried all the less sweeping measures first without success.

My unspeakable gratitude to you all, gentlepenguins, for your kind help and patience! I have learned quite a lot in the past 24 hours: e.g. Linux gives you access to the parts Windows cannot reach; woe betide you if you mess with what you don’t understand; KDE Display Configuration gives a list of several dozen options, not all of which work; and, most important, Linux users are very knowledgeable and helpful. I hope one day to be able to help others and pay it forward. :sweat_smile:

1 Like
11

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