Getting sound from HD4870 to Samsung LNT4065

[ExistNY]

I just built a computer with a blu-ray drive and I want to get sound to play on my LCD TV's integrated speakers. The HD4870 has two DVI slots, but it comes with hdmi/dvi dongle, which seemingly should enable it to pass sound through the card. I believe the HD4870 has an on-board sound processor or something to that effect. It's advertised as HDCP compliant. I hooked up my Samsung LNT4065 to the card, and I get stunning visuals, but absolutely no sound. I fiddled with Samsung's menu, but nothing came of it. I'm just not sure what else I can do. Does anyone know if there are additional drivers I should download? Any help would be much appreciated. Thank you!

 

[ExistNY]

I figured out the issue. I had everything set up right, but I wasn't outputting audio through HDMI.