I had that same result when hooking my older projection big screen TV up to my PC. It was discovered as Generic PnP Monitor (PnP = Plug and Play), and would only go up to 1024x768 which was horrible. I just assumed it was the maximum resolution the TV could support. But since you're TV is connected via an HDMI cable, it might support something higher than resolution. The first thing I would do is try checking the TV's menus for options, changing the input source to something different, or check Nvidia Control Panel and play around with different settings there.