Ubuntu 19.10 still use llvmpip graphics not quadro p2000

Hello, we have a Ubuntu 19.10 that has a nvidia quadro p2000 graphics card. We cleaned and reinstalled the drivers several times, but it still uses LLVM.
nvidia-smi message:
“NVIDIA-SMI has failed because it couldn’t communicate with the NVIDIA driver. Make sure that the latest NVIDIA driver is installed and running”

And the nvidia-setting command displays an empty box.

To install the driver, we did both through the software & update and through the following commands:

sudo apt-get purge nvidia*
sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get install dkms build-essential
sudo apt-get update
sudo apt-get install nvidia-driver-440

and also we try “sudo ubuntu-drivers autoinstall” too.
we have 125.5GiB memory, and processor is intel xeno® w-2195 CPU @ 2.30Gfz x 36
nvidia-bug-report.log (1.7 MB)

Please disable secure boot in bios.