Has anything happened to the laptop recently? a drop or a spill of some kind?
Could be the screen or the GPU. Does the problem change with different angles of the display? are your laptop's fans running? the GPU could be overheating too
thanks for the reply Nothing mentionable happened.. No, the problem doesn't depend on the angle the problem is still there, if i switch the laptop on after switching it off for an hour. one thing which is not noticeable in the video is the appearance of random letters in random places on the screen