add a gpu picker dialog/setting

[PaxtonPenguin]

Is your feature request related to a problem? Please describe.
i'm using a laptop with 2 gpus in it, and the drivers for one of them often crash the system. unfortunately, soundthread uses said crashing gpu when rendering.

Describe the solution you'd like
i'd like an option in settings (or a separate...thing if it's impossible to switch while it's running) that switches which gpu is being used for the output

thanks