game work only on 1/3 of my screen :S

i just renew my gaming time,after 3 months of break,but when i try to play the game,this is how it look
http://www.siz.co.il/my.php?i=5nyizmn2ut25.jpg
any idea what i should do?

btw i did changed my graphic card from the last time i played,it was 8600GT and now its 9800GTS ,if that matter :S

try uninstalling and then reinstalling your gfx drivers.

thanks i install newer graphic drivers and it fix it,thank you for the help