The Witcher 3: Wild Hunt’s 4.01 patch improves ray tracing, but tanks non-RT performance
While the for ’s 4.01 update claim it "improves the overall stability and performance of the game", if you’re not using the recently added settings, it might well do the opposite. I gave the patch a whirl to try out its PC-specific changes – namely a new 'Performance' setting for RT global illumination and a fix for the broken screen space reflections setting – only to find that non-ray-traced, DirectX 12 performance has been utterly knackered.