dashow

A few days ago, I installed a new video card. I went from the original intel chipset to a geforce 6200. After I installed the card, all of my games worked great and everything was going good. But I am not able to view any videos in windows media player. If I try to run a video, my computer starts to run VERY slow and eventually freezes so I am forced to restart. I uninstalled and reinstalled the drivers but that didnt help. Any ideas on what could be wrong?