[FIXED] Unable to uninstall cuda even after purging it and removing the files

Issue

I'm working on a computer on which Nvidia drivers and Cuda were installed by someone else so I don't know the method they used to install them. In the /usr/local/ there were two directories cuda and cuda.10.0. Running nvidia-smi would output:

CUDA Version: 11.0

which made me believe two cuda versions were installed on the system which were causing some errors.

following this question I removed cuda by first doing:

sudo apt-get --purge remove "*cublas*" "cuda*" "nsight*" 

and then doing

sudo rm -rf /usr/local/cuda* 

(I did not uninstsall nvidia-drivers and Driver Version: 450.80.02 is installed). Running nvidia-smi still outputs:

CUDA Version: 11.0

How do I uninstall cuda 11? I prefer to have cuda 10 and I can't find where cuda 11 is installed.

Do I need to uninstall nvidia-drivers as well?

Solution

The nvidia-smi command does not show which version of CUDA is installed, it shows which CUDA version the installed nVidia driver supports, so there is no problem here, just the incorrect interpretation of the output of this command.

Even if you remove all CUDA installations, nvidia-smi would still show the maximum CUDA version that you can use with this driver.

Answered By - Dr. Snoopy