I'm running Windows 7 on an nForce 520 with onboard sound and a Radeon 3870 with HDMI/Audio capability. I'd like to configure my system to use one of these (probably onboard) to drive the external speakers which bracket my monitor, for watching movies, playing games, system sounds, etc. I'd like to connect the other device to my speaker (s/pdif preferred, but RCA is acceptable) and use it for audio streams. This desire raises multiple questions:
One: is there an adapter which will allow me to split the audio signal off the HDMI port and plug it into my S/PDIF coax on my receiver? It seems this would need to permit the video to pass through to my monitor, although I suppose that the audio signal could be duplicated on both DVI ports of my video card. Thoughts? Pointers? Am I insane?
Two: under Linux one can create an ALSA configuration file which basically says "by default, all sounds go to this device, but for these apps use this sound device." Is there an equivalent under Windows 7? I seem to recall that under XP, VLC gave me the option, but I might be misremembering some other way to select output device. At any rate I can't find an equivalent for Winamp. I'm sorta a Windows noob, so please forgive me if I've overlooked something obvious. (when Crucial RMAs my 4GB upgrade I'm gonna virtualize 7 under Debian/Ubuntu... perhaps.)
This is going to be an issue with your mobo maybe it is OS changeable. Anyway you should be able to use your mobo's port along with those on your graphics card. DVI does not carry sound signal, it is HDMI except older and without sound signals. As for HDMI split to S/PDIF I don't think any of those things exist as HDMI doesn't specifically change down as I'm not sure they have specific pins for sound and video.