Upgraded to GTX 1080 and old Post Processing Color Grade settings generate wildly different result.

Working on a VR project in UE 4.12.3, I upgraded 2 Win 7 machines from Quadro K5600 to new GTX 1080 FE cards and updated to 367.18 driver.
Initially everything seemed fine, but several of our Maps seemed 50% darker in Unreal only on the machines with the new GTX 1080 cards.
After reading several posts about turning VXAO off because it may not be implemented for Pascal cores yet, I checked and we didn’t have that turned on.

After further dignosis, it appears that the results of Post Processing Color Grade settings has a much more extreme result for the same values on 1080 card vs the non-1080 cards.
In particular an artist had set Contrast to .6 .6 .6 in the project weeks ago and while that made a relatively beneign change on the non-1080 systems, that same value generated a 50% darker image in the 1080 version with all other things being equal. (Actually not quite equal, the machine where the color grading was done, was Win 10 Titan-x configuration, so it is a possibility that Windows version (7 vs 10) could be related as well. (We’re judging the color change not just via monitors (which could have different calibrations) but also how the scene looks on the SAME VR headset attached to each machine.

For now, we’ll turn off Color Grading and use it only if necessary closer toward the tail end of the project (perhaps 1080 driver or UE patches will address by then).
Just thought this was worth sharing.


I’m willing to bet this is a Driver issue more than something on UE’s end. Hard to tell though to be honest. Give it a couple of months to let the drivers settle and have nVidia work out the glitches, but I’d also post this on Answerhub too.