HDTV monitor stopped working suddenly

[Riley_B]

hello, I use my vizio m220va hdtv as a monitor for my desktop as well as a tv and just a few days ago, after i used the hdmi cable I generally use to connect my desktop to my tv to instead connect my laptop to a different tv, my vizio just stopped displaying when I reconnected it to my desktop. all it shows now is "Not Support!" It is connected via hdmi to my radeon 4600 graphics card. it's not the hdmi cables, I have two, and I checked, they both work. it's not the hdmi ports on the tv, they both work for both my laptop and my ps3. it's not the desktop because it hooked up fine via HDMI to another tv also via hdmi and it worked fine. I uninstalled/reinstalled the graphics drivers, and both my graphics card and my computer are aware of the tv's existence and say it is functioning fine. I did a system reset on the tv, and I've tried messing around with different resolutions and that didn't help, and i took the graphics card out, cleaned it off and put it back in the desktop.
nothing has worked.
any suggestions?
thank you very much.

 

[unksol]

change the resolution you are outputting to the tv to match its specs

 

[Riley_B]

It was correct to begin with, and I've changed it to nearly all other options and back again, and it didn't fix it.

 

[Riley_B]

also, in addition to the blue "Not Support!" screen, there are also occasional switches to bright multicolored lines across the whole screen for a few seconds at a time before it switches back to the blue