Ever since I've upgraded to Win 10 (from 8.1), R3E was basically unplayable at casa de moi. Specs: i5, GTX660, Win10 Symptoms: - mouse lags in general menu, combined with a not very fluid background animation (the Mercedes) - in the race menu (when you're ready to go on track), a lot of screen flickering. - and when on track...a stuttering fest. Basically, the screen was freezing for 1/10th of a second every second. So I tried a lot of stuff. Everything in the option menu (vsync, AA options and so on). Unplugging all my USB devices. Nothing fixed that. I even did a full, clean factory reset of the OS (that was long overdue anyway) but to no avail. But today, I finally got the Eureka moment: I disabled my second screen. Software-wise, from the nvidia Control Panel. And it fixes the issue - Every time. 2d screen on, stutters. 2d screen off, no stutters. To be precise - the 2d screen is my TV that I hook up the PC via HDMI, so the screens are cloned, it's not an extended display.And my desk screen is hooked up via DVI. So, while the workaround works, it is not ideal, as it's a tad bit too tedious for my taste. To be fair the R3E, it seems Win10 and/or nVidia do not like as of now multiple displays (or at least, my own setup). While I don't have as much as an issue with other games, there are still slight annoyances. For example, when I sometimes quit or alt-tab out of Starcraft, I do not have any display on my screen until I turn it off and on again, just as if Windows was "forgetting" about it.