I connected my Inspiron 1520 to a Coby LED via VGA. I changed to resolution and pressed Fn+F8. It worked, laptop screen went black and tv displayed the screen. I came back a few days later, did the same thing, labtop screen went black but this time I got a "not supported" on the tv, even though my resolution was changed appropriately. I restarted the computer, changed the resolution, pressed Fn+F8 and absolutely nothing happens. The screen doesnt even go black and no signal is sent to the tv at all. It worked the first time, got "not supported" the second time, and "no signal" at all the third??? Any ideas please