I have a dell Optiplex 980, running Windows 7 and Office 2007 Pro. Suddenly whenever I open Word the screen goes black and then comes back on partially pixelated, almost looking like a 1990's version of windows. It changes the entire OS just by opening Word. When MS Word is then closed the screen goes black again and then reverts back to the correct looking Windows 7. None of the other Office programs do this, only when opening Word. I tried running a repair on Word, no change. I removed and reinstalled the entire Office suite, no change. What is this?????? How can MS Word effect the OS like that?