I'm glad you found a solution. It's a weird one, but hey, if it works for you, great!
In my laptop I also have multiple graphics cards, an Intel and a NVIDIA one. And there's something called NVIDIA System settings or so, where I can select an application/program and select which graphics card it should use. Maybe there's something similar for AMD cards, too? So, instead of turning off your AMD card completely, try finding if you can select a specific graphics card for a selected program. Otherwise you will always have to turn your AMD card on and off if you play different games.