it's attached to the tv with a 10m vga cable so i dont think that's the problem.
That'll be the issue right there. VGA inputs on most HD sets are notoriously picky about what resolutions they take. You'll be lucky to even get full resolution (720p that is) from it using that cable, but if you can get 1280x720 then stick with that.
The HDMI and component inputs will probably handle 1080i just fine though. I use the component out from my geforce 8800 card now for precisely that reason. It'll accept pretty much any resolution i throw at it up to 1920x1080 without any fuss.
Switch back to VGA though and its a world of pain just getting it above 1024x768.
Edited by manuel_garcia at 13:03:14 03-05-2007