I tried googling this and can't find anything about it maybe you guys can help me. I just replaced my old Asus 1080p 23 inch monitor with the LG 27UD68 4k monitor. The monitor has excellent picture but anytime I watch a full screen video whether it be in the windows 10 native video player or youtube fullscreen, the video starts stuttering as if its rapidly switching between windowed and fullscreen mode. I just noticed that if I just maximize the video and leave the borders, the video plays fine. Also if it's full screen but I leave the mouse highlighting the windows taskbar it also plays fine. No idea why this is happening. My pc is a MSI M5 z270 motherboard with an i5 7600k at stock speeds and the monitor is connected to a gtx 650 with a dvi to hdmi cable. Any help is appreciated.