Everyone online says the difference is like 5-10%. But in my experience using on nvidia rtx 20 it's always 20-25% fps loss compared to windows. Regardless whether i'm bottlenecked by GPU or CPU, on DX11 and DX12 games, it's always 20-25% FPS defecit. Is that expected?
Using Wine-GE 8.1X with latest dxvk, d3dvk with bottles manager on fedora with nvidia drivers.
I’ve found that it depends heavily on what game you’re playing. I wouldn’t say 20% loss is uncommon.
You could try using a kernel tuned for gaming but it probably won’t make up the difference.
Honestly you’re probably better off not comparing to Windows. You’ll often fall short performance and feature wise.
Edit: I’ve also found that people tend to oversell Linux. We desperately want more users but exaggerations do more harm than good.