Very irritating issue here. I tried running a game "Assassin's creed:Syndicate" on my Asus ROG G551VW at a resolution of 1600x900 and it runs on partial screen even when I have fullscreen option checked. It will only occupy full screen if I run the game in 3840x2160 resolution but that's not feasible. Too much lag...unplayable. I have 3840x2160 native resolution. I realized that problem lies in display dpi settings in compatibility option. See the images: Game not running on full screen: Full screen option is checked as follows:: I realized that "Disable display scaling on high dpi settings" was checked and I needed to uncheck it. So I did. The game ran on full screen for some times...opening credits and all..but then after that returned back to old stage. Then when I quit the game and check settings again, that thing was checked by itself! Windows did that automatically. Then I changed my native resolution to 1600x900 and game ran on full screen. But then I thought if it was glitch in the game or my laptop. So I went to my neighbor in my college hostel who owns lenovo y50 with 1920x1080 native resolution. He ran the game and it opened in full screen on 1600x900. I wondered how? I soon realized by checking that "Disable display scaling on high dpi settings" remained unchecked on his machine and windows was not automatically checking it. So I want to know how can I uncheck "Disable display scaling on high dpi settings" so that windows can't automatically check it again ? Also if there is any other solution please do tell. Thanks in advanced... Edit: If I posted in the wrong section please do move it. Again sorry for inconvenience..