How old is this Dell Laptop? I worked on a relative's really old (Core2-era, single-core Celeron, 1-2GB RAM, Windows Vista) laptop, put in an SSD and a fresh copy of Windows 10, well, wouldn't you know it, the ancient video drivers that got installed, didn't handle monitor sleep/wake, and lid open/close properly, such that it was possible from opening and closing the lid, and letting the screen sleep, to not be able to wake it up again easily. Had to use ALT+F4 to shut down apps, then hit ESC, hit ALT+F4 once more, hit ENTER to Shut Down, then boot the PC up again.