you mean ou want to connect INTO the pc or out to the home theator?
I currently do the later with my own Sony 5.1 home theater setup... it works just fine. You just need to match output to input. depends on your theater unit. In my case i use an optical cable... works beautifully. Of course that's not an option for you (optical is limited to 5.1); but a digital audio connection should work... not sure about HDMI... depends.