All three HDMI input jacks of my LG Plasma 50PK750 TV stopped working ("no signal" msg displays instead of screen from laptop). My highspeed HDMI cable works just fine when connecting my Toshiba Satellite laptop to another TV. So it's not the laptop and not the cable. What could have happened with the LG TV? The fourth HDMI input that is permanently connected to a Bluray player is just fine.