This caused by the video cable wearing out, cables are made of stranded wires so that the cables can flex. A problem happens when either the insulation wears off of the cable or a few broken strands poke through the insulation and short out on the outer shield. Check on the Lenovo site to see if the warranty is still valid, if it is then contact them to arrange repair. If the laptop is not in warranty then check out the take apart sections on ifixit.