I have a powerful nVidia GPU, an old and slow AMD GPU, and a motherboard with two PCIe slots.
I also have an old, obscure video game which has graphical glitches under nVidia cards. It's a rhythm game which requires good audio/video sync, so using a Virtual Machine is out of the question. It works fine under my old AMD card.
What is the easiest way to switch to my AMD GPU before running this specific game? Anything quicker than manually opening up my computer and switching out the cards will be an improvement.