Pardon then.. Were You perhaps toying with windows compatibility settings for the executable? and/or DPI/scaling in windows? perhaps there's the issue? I use the native DPI settings, but it's easy to change this in windows 10, *even* by accident. Simply You let's say pressed control and toyed with the mouse wheel, and it's already screwed up. If so then You could check Your NevadaHD.exe's compatibility settings. switch everything off if you use sfall, and set the DPI settings to use default settings when launching the game ( there's a separate button for it in newer win 10 builds for it, i haven't personally checked this but I've read somewhere that DPI can be an issue with other old games and alt-tabing, so maybe it's similar case. Afterthought after looking up the thread agin Judging by the screenshot You have some issues with game refresh rate ( the settings for this are usually in f2_res.ini) it says 1280x720x1 where the last number after the second "x" is usually the refresh rate. In your case it's "1Hz" so either it's integrated card settings or you have an Nvidia and a shitty driver, or some silly energy saving mode that lowers the framerate of background processes... this may be an issue as well so try to check out this one too..