i had the same problem you were having after numerous attempts to solve the problem and combining some logic (my hdtv only flickers when I plug it in to charge, when it was not on charge there was no flicker) so the power outlet must be the source of the problem.
First, if your tv still flickers even tho you are not plugging it in charge then this probably isn't the solution and it may be your video card.
My solution(both worked for me): plug your tv or your laptop charger on to a separate power outlets. If you are not within reach of another outlet then on the same power surge as your tv, add a outlet splitter or adapter to your laptop charger before plugging it into your power surge.
i have a new toshiba satelite with vista. when i hook the laptop to the TV with vga cables, the picture comes out very very nice. BUT THE TV SCREEN KEEPS FLICKERING! i have tried many combinations of resolutions and refresh rates or w.e and cant get it to stop the flicker....someone please help me!