Phillips 42" plasma HDTV hdmi resolution problem!

I recently purchased a phillips 42" plasma hdtv with what is supposed to be a resolution of 1280x768 according to the detected display under my catalyst drivers on my x1300 (media center pc), and I am also plugged in through dvi->HDMI. My problem is that the resolution is bugged some how.

I am not cloning or duel displaying, im switching the display completely to the hdtv, and at any resolution i set it at, whether it is 1024x768 or 1280x1024, or whatever, the tv is like cropping the screen, and as I drag my mouse, different parts of the screen become visible.

I have had this problem before with an older computer ,and a regular tv when doing duel display and not having resolutions match. But this is supposed to be a direct monitor hook up. I don't see any options on the tv itself to fix this problem, and its a brand new video card so I havn't really experimented with many of the options on the card, but I don't really know where to start with things.

Can someone please give me advice to get this fixed asap!!!

P.S. The model number is on the back of the mounted tv, and I can't really remember it.. it ends with a 37 i think.

Hhhmmmmm.... I think it's broken. Better put that thing back in it's box and post it to me....