Hi all. I have tried everything I know to try and resolve this problem. I have an older dell dimension e520 running Xp media center with sp 3? I have only upgraded the memory to 4gb, and installed an evga 8400gs graphics card. When I first installed it, I had sound through the hdmi cord to my tv. Couple of days later when I turned it back on there was no sound. I've checked in device settings and there are drivers installed, and it says they are working. I have uninstalled system sound drivers, sp3, and clean install of newest drivers from nvidia site. Still no sound. Reinstalled sp3, and system sound drivers, It does not give me the option to turn on hdmi sound in neither sound settings nor nvidia control panel. But the system shows the drivers are installed and working correctly. If anyone has an idea on how to get this working again I would greatly appreciate it. I don't do much with this pc except watch movies on it on my hd tv so buying new parts is out of the question.