[Solved] Titan X for CUDA 7.5 login-loop error [Ubuntu 14.04]

[Shen_H]

When I add “export PATH=/usr/local/cuda-8.0/bin${PATH:+:${PATH}}” to ~/.profile, the login loop happens, and all PATH lost. all of bash, cat, python can’t be found.
After comment it out, login works, but nvcc can’t be found.
I am new to Linux. how to set the path properly?

[Robert_Crovella]

export PATH=/usr/local/cuda-8.0/bin:$PATH

[Shen_H]

export PATH=/usr/local/cuda-8.0/bin:$PATH

Thanks.
Somehow, it fixes my login-loop error, but I haven’t tested whether my CUDA works properly.

[kiranvaidhya]

I don’t think this is completely solved yet. I’m facing fresh problems on Ubuntu 16.04. I tried this solution. The login loop is avoided. But my devices are not getting detected by any libraries. When I hit nvidia-smi, instead of the device names, I’m getting ERR.

True

@txbob

@NeuroSurfer

Maybe I missed something?

Update: I will re-install adding the --driver and --no-opengl-libs flags (although my .run file never prompted be about this…)

Yes, you missed the part where I said:

“During the install of the runfile, select the command line option to not install OpenGL libs. If you’re not sure what that is, use --help on the runfile install command line to see the command line options, then re-run with the command line option to disable installation of the OpenGL libs.”

This is a (the) critical step to avoid the “login loop”.

And if you’ve already installed this way, a reinstall may not fix anything. You may need to start over with a clean load of the OS.

I reinstalled the OS and re-ran everything same as before adding the --no-opengl-libs flag. This is the critical part. I would like to add something else though! I did not install have to install the NVIDIA driver explicitly first. I ran the cuda.run file instead, and said yes to install the NVIDIA driver when it prompted me to. I feel like doing this in one straight run made everything way easier. Thanks for everything!

Post of final script and solution

0. Download your relevant CUDA.run file: mine was: cuda_7.0.28_linux.run
   Note, that once again this install is if you purely want to use your graphics card (Titan X) for GPU/CUDA purposes and not for rendering.

Also run: $sudo apt-get install build-essential

1. I start off with the regular GUI and Ubuntu working with no login problems.

2. No need to create an xorg.conf file. If you have one, remove it (assuming you ahve a fresh OS install). $ sudo rm /etc/X11/xorg.conf

3. Create the /etc/modprobe.d/blacklist-nouveau.conf file with :
   blacklist nouveau
   option nouveau modeset=0

Then $sudo update-initramfs -u

4. Reboot computer. Nothing should have changed in loading up menu. You should be taken to the login screen. Once there type: Ctrl + Alt + F1, and login to your user.

5. Go to the directory where you have the CUDA driver, and run
   $chmod a+x .

6. Now, run $ sudo service lightdm stop
   The top line is a necessary step for installing the driver.

7. I run the CUDA driver run file. *Notice that I explicitly don’t want the OpenGL flags to be installed:
   $ sudo bash cuda-7.0.28_linux.run --no-opengl-libs

8. During the install:
   Accept EULA conditions
   Say YES to installing the NVIDIA driver
   SAY YES to installing CUDA Toolkit + Driver
   Say YES to installing CUDA Samples

Say NO rebuilding any Xserver configurations with Nvidia.

10. Installation should be complete. Now check if device nodes are present:
    Check if /dev/nvidia* files exist. If they don’t, do :
    $ sudo modprobe nvidia

11. Set Environment path variables:
    $ export PATH=/usr/local/cuda-7.0/bin:$PATH
    $ export LD_LIBRARY_PATH=/usr/local/cuda-7.0/lib64:$LD_LIBRARY_PATH

*Change depending on your cuda version.

12. Verify the driver version:
    $ cat /proc/driver/nvidia/version

13. Check CUDA driver version:
    $ nvcc -V

[Optional] At this point you can switch the lightdm back on again by doing:
$ sudo service lightdm start.

You should be able to login to your session through the GUI without any problems or login-loops.

14. Create CUDA Samples. Go to your NVIDIA_CUDA-7.5_Samples folder and type $make.

15. Go to NVIDIA_CUDA-7.5_Samples/bin/x86_64/linux/release/ for the demos, and do the two standard checks:
    ./deviceQuery
    to see your graphics card specs and
    ./bandwidthTest
    to check if its operating correctly.

Both tests should ultimately output a ‘PASS’ in your terminal.

16. Reboot. Everything should be ok.

[MrGabbo]

I was able to install the drivers and solve the login loop problem in Ubuntu 16.04 + Nvidia Quadro 620M. Nevertheless, I’m still not able to get any output on the VGA/HDMI ports. Despite the fact that all the excutables work, I exported the environment variables successfully, I can check nvcc version, I can use CUDA libraries, etc, I think Ubuntu is not really using the NVIDIA card to produce the graphics…

Honestly Nvidia, is it that difficult to develop working drivers? I am not talking about completely optimised, full throttle drivers, but…please I just want to have a VGA output in linux and actually use the card I bought from you…

[Tamizh]

Error message i got after i run the nvidia…384.90.run. please install the linux-headers-3.13.0-43-generic package or use the --kernelsourcedir option to tell dkms where it’s located

[alvin.yeo]

Old post but THANK YOU for posting these complete instructions. +1
This is the ONLY solution which really helps to solve the login loop issues on Ubuntu 16.04 & 18.04 after struggling for one whole week!
Appreciate it!

[mwz7]

Thank you so much! These are the best instructions I found online after 2 weeks. Only difference I had in the system I was using was the display manager, and using sudo systemctl stop gdm3 and sudo systemctl start gdm3 where your lightdm commands were worked.