Sound over HDMI?

Quick question, can a desktop graphics card put out sound through its HDMI port? Otherwise I don't know how to get the sound to come out through my stepdad's new TV's speakers without going to an unacceptably lower quality component video connection. I'm building a HTPC for him using as many old parts as I can other than the graphics card and blu-ray drive.

Yes, many recent discrete cards can do this. I just bought a Sapphire 4670 DDR4 from Newegg for my HTPC. Cheap price and can do anything including some decent gaming. It's also SILENT.

This one: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102818

I have an ATi 4350 that has an HDMI output and it pushes sound through to my monitor speakers. The drivers have an audio codec or decryptor in them that activate the port so to speak. It is also running my dual displays right now too. Doesnt game very well at 1920x1200 lol, but it has good hd playback.

Lol, cool. And here I thought not even my HD4850 could do this.