@RedPhantom The issue in the past with CPU renders looking different than GPU render was down to the clamp settings. In CPU it turned this off and (no clamping) so CPU would calculate for ALL the lighting while it turns clamping on for GPU and you can experiment with how much clamping there is. The issue was that it was never really explained to the users this would have a profound impact on SOME renders. It matters how many lights you have and how small and intense they are. It took me more than a year to figure out what exactly was going on with the renders just because it wasn't all renders. Very puzzling.

W10, Ryzen 5 1600x, 16Gb,RTX2060Super+GTX980, PP11, 11.3.740