Can't install nvidia drivers on Debian. RTX 2060 super
 

After installing Debian 12, everything is lagging a lot, the cursor lags, scrolling pages is laggy, YouTube also lags, so that's why I want to install the drivers for the video card. I did everything according to the instructions.
But after rebooting I get a black screen, or to be more precise, after entering the password, after which I am redirected to the login page again. I've been trying to solve this problem for 2 weeks but nothing works. I'm new to Debian so don't judge too harshly.
I tried to install the driver on 1060 6 GB, nothing worked, now I have a 2060 super, and the same black screen, and same lags with nouveau. Also, since the 1060 6 gb and 2060 super lag the same, I thought Debian was using the processor's integrated graphics, but it seems not. Pls help. Btw sorry for my english

I can't upload a file with logs here, to show all dmsg output(idk how to attach a file), so I'll show the output of

Looks like the nVidia module is loaded and the gui is messed up.

What's the ~.xsession-errors have to show...

I've been trying to find where .xsession-errors is, but I can't find it

Should I move this thread to Linux - Hardware?

Hi, it's a hidden file... use you user name...

/home/glenn/.xsession-errors

Okay, so, before entering commands , I cleaned the contents of the file by doing I installed the drivers via rebooted, ctrl+alt+f2
It's empty(

Why clear the content? Isn't that what you need to check for errors and failures.

After X starts, there may be messages.

Being that the .Xsession-Errors file is a hidden file the OP needs to issue the command in the code block ay yhe bottom of my reply.

If you do not enter root, then ls -a will not show the xsession file, I didn't know that and that's why I spent a lot of time searching for the file, but thanks

I was cleaning the file because there were a lot of past sessions and I was confused which one was the right one. And I was also confused, because not every session is recorded, this time I did not erase anything, installed the driver, restarted the computer, and checked the xsession file, I typed the same commands, and it was empty, maybe there is some analogue? I am so frustrated with this problem and thank you for your help

OK, I really don't know what to do now, without that file I'd be lost.
one thing, all the sessions are appendended to the end of the list in that file.

Also, grep may be missleading sometimes, as the system may find and load after the error message.

Instead of moving your post to hardware or linux-desktop, restate your question for the best exposure.
A person better experienced than me may see it.
p.s. - Have you tried a Live-distro to see if it works there?

All the best.

One more thing, at the login page (sddm?), is the page white?

if so, move your mouse to the bottom left area, is a selection box for plasma-x11 OR Wayland,

select Plasma-x11 and enter your password.

I always get the white page until I install a theme for sddm.

You may disregard this if you're not using sddm. btw, X starts early (sysinit) now-a-days.

p.s. - is seatd installed? (the .xsession-errors file would show an error if so)

You realize su switches you to root? So don't do that.

~/ maps to your $HOME folder. So if you switch to another user, that wouldn't likely refer to your own home folder anymore, depending on how su is setup to pass variables, etc. And if it did still refer to the original users home folder, if you wrote to that file as root, you might mess up permissions to be able to write to it yourself later. So just don't.