My laptop screen has recently started to freeze and discolour (white and/or purple) notably, it's only the screen, the computer still works otherwise (I' am typing this mostly blind) and I can usually do a short term fix by moving the angle it's at a little. I have tried both tightening and loosening the screws around the screen, and when I took it to my local computer repair shop he cleaned it of dust and viruses. It's an Asus E502S running Windows 10, it's not quite 2 years old yet.