latest update breaks nvidia-prime and produces blank screen

[Soft Ginger]

I'm currently using a laptop with optimus technology and NVidia graphic card. Last year (2013) I installed NVidia-prime and it worked perfectly. However, the very recent update (2014/1/29) broke NVidia-prime. The screen turned into complete blackness after Ubuntu splash screen (the purple one), and was even not showing cursor. However, from several difference behaviors I am sure that everything else (like terminals, keyboard inputs and even games) is working properly after login.

Ubuntu version: 14.04 (Trusty Tahr)
nvidia-prime version: 0.5.4

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Marcin Sągol (soee)]

I can confirm this issue on nvidia-prime version: 0.5.5 also but some say it works (https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-331/+bug/1268771)

Running Kubuntu 14.04

[Soft Ginger (soft-ginger)]

After I update nvidia-prime to 0.5.5 it works. I just have no idea how this bug would ever appear.

[Alberto Milone (albertomilone)]

@Marcin: please attach the following files:

1) /var/log/nvidia-prime-upstart.log
2) /var/log/prime-offload.log
3) /var/log/prime-supported.log

4) /var/log/lightdm/lightdm.log
5) /var/log/lightdm/x-0.log
6) /var/log/lightdm/x-0.log.old

Note: if you can only use the terminal, you can install the "pastebinit" package, then type "pastebinit $name_of_the_file" and paste here the links that the program will print.

[Marcin Sągol (soee)]

@Alberto
1) /var/log/nvidia-prime-upstart.log -> http://paste.ubuntu.com/6875487/
2) /var/log/prime-offload.log -> thers no such log here so i posted /var/log/prime-switch.log -> http://paste.ubuntu.com/6875491/
3) /var/log/prime-supported.log -> http://paste.ubuntu.com/6875496/

4) /var/log/lightdm/lightdm.log -> http://paste.ubuntu.com/6875502/
5) /var/log/lightdm/x-0.log -> http://paste.ubuntu.com/6875503/
6) /var/log/lightdm/x-0.log.old -> http://paste.ubuntu.com/6875505/

So as i said before my booting ends with black screen. Tham if i press CTRL+ALT+F1 i can switch to console where login command shows up

[Alberto Milone (albertomilone)]

The fact that /var/log/prime-offload.log is missing, means that the program that is supposed to tell the system to use prime is not being used.

Please attach the following files:

1) /etc/lightdm/lightdm.conf
2) all the files in /etc/lightdm/lightdm.conf.d/

You can still use pastebin as you did before.

[Marcin Sągol (soee)]

@Alberto

today i have installed some updates from proposed. This broke my system (xorg etc.) so i had to do a fresh 14.04 installation. I hav einstalled also nvidia 331 and this ad dependency installed nvidia-prime. All seems to work just fine now so maybe the problem was with some old configuration on previous installation (update from 13.10 -> 14.04)

[Alberto Milone (albertomilone)]

Yes, that's exactly why I was asking about those files.

[Otomo (otomo)]

That happened to me when I upgraded from 13.10 to 14.04 stable. But no solution worked for me.. It's very serious as I couldn't work now.

I tried to use nvidia 331 drivers, prime select nvidia and Intel, purge all nvidia drivers, startx... But always all black except terminal. I readed all similar bugs out there but almost all are dated from January and February.. I writing this from my smartphone after 2 days fighting...

I have a laptop with a nvidia 765gtx. The previous kubuntu worked almost fine with the 319 driver (I also tried to use that driver).

I never installed a nvidia driver out of official repos

[Otomo (otomo)]

I will try to do a fresh install in a few hours and I will report after.

[Otomo (otomo)]

With a fresh install worked perfectly (well, as it worked before, I have a couple of minor problems that I will report as other bugs).