ATI All-In-Wonder video card locking up

I have a ATI All-in-Wonder X600 Pro video card. Am using ATI’s Multimedia Center 9.08. Windows XP, Service Pack 2. Multimedia Center (MMC) locks up in TV Mode after several hours of operation. Not sure how long. To test it, I let it run over night. In the morning, MMC is locked up. Unable to kill the task via Task Manager. Have to reboot PC. Motherboard is Asus A8V-E Deluxe. It is a new PC. I installed newest software and drivers from ATI website. Did not fix problem.