hi
not sure where to go with this: for the last couple of months my Dell laptop screen, out of the blue, has been flickering with fine horizontal red/yellow lines, a couple of seconds at a time. These occurences are often separated by weeks. Nothing else seems to be out of order and the computer functions normally while the screen is discoloured in this way. Help! Am worried it's going to get much worse, as today it went on much longer (right now actually).

thanks