For the Dgpu (Dedicated) and Igpu (Integrated):

Read this documentation for the installation:

Now, if you face an issue like:

[ 93.124290] [ERROR]Cannot access secondary GPU - error: [XORG] (EE) Unable to locate/open config directory: "/etc/bumblebee/xorg.conf.d”

— Now, make a directory in the: /etc/bumblebee with named as the “xorg.conf.d”

              `sudo mkdir - p /etc/bumblebee/xorg.conf.d`

Change the mode of the file:

             `sudo chmod 755 /etc/bumblebee/xorg.conf.d`

Now, create a basic configuration file:

        `sudo nano /etc/bumblebee/xorg.conf.d/20-nvidia.conf`

Paste, this given below script:

Section "Device" Identifier "DiscreteNvidia" Driver "nvidia" VendorName "NVIDIA Corporation" BusID "PCI:01:00:0" EndSection

Now, press Ctrl + X and then “Y”, and save the file.

Now, restart the bumblebee:

      `sudo systemctl restart bumblebeed`

Now, try to run the:

     `optirun hashcat -b -d 1`

To ensure that your NVIDIA’s GPU working or not try to run the -

          `watch nvidia-smi`

This will ensure that you’re GPU is running.

— In the Second Screen-shot I’m using - watch nvidia-smi to ensure that - GPU is working perfectly fine.

— If all the things are loaded successfully, then it means you are eligible to use dgpu for the processing.

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