As I said above it's a common fault with laptops. Sometime ago my Sony laptop had the same symptoms as yours. Just don't open it too wide and it would be fine. After 9 months of suffering this problem, decided to get it looked at and sure enough it was the wiring loom. It may not be that problem with yours, but it is likely to be. Whether you persevere with problem and maybe continue to prop the front of your machine up with books or with what ever to view the screen at a better angle is down to you. One thing for sure, it won't mend itself.