well, i downloaded some 1080p content from microsoft and i figured i would hook up my 5084 like i hooked up my 42 inch lcd from my tower. well im using my laptop this time, i hooked up the plasma via the extra monitor jack on the back, a usual monitor connection and it kept saying non supported mode.
i turned the resolution down and it still wouldnt work. i tried all resolutions and it still wouldnt work.
what am i doing wrong?

What laptop?

Most/all that have a VGA port let you have both your laptop screen on and the external monitor on at the same time with different resolutions. When you change the res you have to make sure you are changing the res on the external monitor and not just your laptop screen.

a dell latitude d610
i did this.
it still wont work
i dont know what the hell is wrong with it but its really irritating.