Aight, a cousin of mine have some HP AM2 machine. It's pretty good. It used to have a x1650 SE graphic card, but it kinda sucked, so he bought the HD4730 at a good price instead, together with a 630W PSU. He did not uninstall the drivers for the x1650 before installing the new card. Now the onboard sound device (some Realtek HD Audio) is simply not there. It doesn't exist. What does exist is some ATi HD Audio something something, but that doesn't provide sound either (I guess it's supposed to go through the HDMI?). Everything else works, it's just that the on board sound is nowhere to be found. So, what happened? I know it's not too good to simply install new drivers on old ones, but that shouldn't mess with the onboard sound, should it? Also, he lives like ~2000 miles from me, so I can only give him phone support. Thanks for looking!