How do I permanently enable the external video card in Windows?

Set default graphics card for your programs:

  1. Right-Click and Open the Nvidia Control Panel from the Desktop.
  2. Select Manage 3D Settings under 3D Settings.
  3. Click on the Program Settings tab and select the program you want to choose a graphics card for from the drop down list.
  4. And select the Preferred Graphics Processor for that specific program from the drop down list.

and

Set your default graphics card (NVidia)

NVidia