My nVidia card was enabled and working fine, but then I tried to use
nvidia-prime, but never got the PRIME settings in
nvidia-settings. I found that there is a bug regarding this and decided to revert to my previous state.
For this, I uninstalled all nvidia stuff (
apt-get purge nvidia-*), reinstalled
nvidia-331 and went into my BIOS to use the nVidia card only (no optimus or anything).
Now it looks like nVidia is being used again, but I think this is not true. "About this computer" as well as "Additional Drivers" tell me that it is active and using the proprietary driver.
But if I, for example, start TMNF (Trackmania, a game) with Wine, it tells me it can't find the video card performance and when I start playing the game, it is very laggy and has graphics glitches – things that definitely weren't there before.
Another thing that makes me believe something is wrong: When booting, I get the grub screen asking what to boot and one screen asking me to unlock my hard drive. When using the Intel card, these screens had high resolution; using the nVidia card made them have poor resolution. In the current state, the first screen (grub) has poor resolution, but the unlock screen has high resolution as if it switched from nVidia to Intel during booting.
Lastly, when opening the
nvidia-settings, I get very little information/options, which usually is the case when the Intel card is active.
Does anyone have any ideas what I could try or how to fix this? Reinstalling the system is something I'd really like to avoid.
Update: I tried several methods described here and all tell me the nouveau driver is being used, not the proprietary one. If I boot the kernel with
nomodeset, I am stuck with super low resolution.
Edit: My setup: Lenovo T530 with Ubuntu 14.04.