How to use dedicated GPU in dom0 to display?

I don’t ask GPU passthrough.
I know Qubes OS only use CPU to render but use GPU to transfer rendered data through What are usages of GPU in Qubes OS?

Reasons you may want to do this:

  • Faster transfer speed. So you can use higher resolution or more monitors. Dedicated GPU is faster because it have bigger frequency, faster memory and other factors.
  • You can buy cheaper CPU without integrated GPU

Suppose driver of dedicated GPU is installed, which is complicated if you use Nividia card, you can reference Nvidia driver installation. Driver of old AMD card is included in Qubes OS kernal, you don’t need to do anything in this situation.

Then how to make Qubes OS only use dedicated GPU instead of integrated GPU? You don’t need to do this if you don’t have integrated GPU but many PC or laptops have integrad GPU.

I think rd.driver.blacklist=nouveau will only diable Nividia driver but it can be seen in many places.