I just spent the last 3 hours trying to figure out why enabling SLI caused my video cards to not output video. So I took out my video cards and put in a GTX 660. No perf diff in 4.11.1 still 89 fps in my test scene. I know that’s not very helpful to you, but it’s the only information I have been able to glean from my trials on this one :. I do hope someone can get you some useful info soon