Not really 560 specific but I thought I’d shine a light on this, with Above 4G decoding enabled in BIOS, Control doesn’t utilize the full GPU.
If I disable Above 4G Decoding in BIOS, it utilize the full GPU in the game (just disabling Rebar alone does not help).
See screenshots.
4G enabled (73% GPU usage):
4G disabled (100% GPU usage and there’s roughly a 15FPS gain):
I’m not sure how many games are affected by this but it’s not a general solution just to disable Above 4G decoding since it usually makes things worse.
I have no real idea if it’s the driver, or possibly vkd3d-proton that’s causing this.
(Windows is not affected)