I have a problem with my HP Laptop that may or may not be serious. Sometimes, but not everytime that I open or turn on the laptop, I get a flashing line at the bottom of my screen. It flashes off and on and is sometimes very thin and sometimes 3/16 thick. It streches from side to side and is at the very bottom of the screen. The color of the line is a light green. Do I possibly have a screen that is getting weak? Any help would be greatly appreciated.