# you have a problem with GMUX chip. Perhaps it is LVDS connector. To sure diagnose press lightly with your finger on LVDS connector, when image become clear, it is the LVDS cable.. and you must clean it with alcohol and fine brush.
# when you press lightly the GMUX chip and lines dissapear, then you must exchange this chip. This IC has a solder joints problem, that after years fall connection between chip and Logicboard, so it must be reball, or exchange and programmed(from old one) with new one..