AstaLaVista

OK, I don't know much about ATI but I just read this on some other thread and this may or may not help you.

Since your Video card also comes with HDMI audio, I think your best best is to DISABLE the onboard audio in your Bios and let the Video card with sound take over. It may not work but, at least, is some other solution you can test.

Also, you may have chosen some wrong options on your realtek control panel and this is why the analog is not highlited. Your ATI and Realtek might have some sort of conflict with which one is the master and which one is the slave.