trouble with resolution on widesreen hdtv

I'm having trouble attaining the correct resolution on my Mitsubishi 55" HDTV (WS55413) used in conjunction with my MSI ti4400 video card, dvi connection. I have msi motherboard, 512k ram with winXP. I recieve the windows screen but about 2" of every edge is cut. Mitsubishi knew of know device driver, they said it wasn't built to be a comp monitor but it works. Right now I'm using generic tv driver. Any ideas? Yes I agree I think it needs a specific device driver but many hours have been spent in this endeavor with no luck at all.