I recently purchased a Studio XPS 435 Desktop which came with the Nvidia GT220 with HDMI out and the Soundblaster PCI Xfi soundcard with Spdif in/out. I also recently upgraded to Win 7 Pro and updated drivers as well. Currently I'm trying to incorporate the machine into our home entertainment system and have connected the computer to our Sony LCD TV via HDMI and successfully have a picture there. However I cannot get the digital audio to work with applications e.g. iTunes or Windows Media Center. I have connected the computer via the soundcard to the TOS input on my receiver and confirm I can send OS sound but am stymied by the inability to get programs audio to play. My receiver is a Marantz SR-700 and it will handle DTS, Dolby Digital audio and PCM.

I've looked at the Nvidia site and it indicated the GT220 sends the digital audio to the motherboard and not over the HDMI cable. However when I connected the TOS to the Spdif on the board I got no output. Perhaps Dell redirected the audio to the soundcard? The bottom line is I need some assstance configuring the digital audio out. I hope someone has been successful and can share your experience.

Thanks in advance!

(update) - I got two channel PCM output working with programs by making the Spdif the default sound device. I still cant get 5.1 program audio nor do I see that option in the soundcard settings. All of this is after updating both drivers.

(update II) - I feel like such a noob! If you seem to be having the same issues, I recommend you visit the Creative Forums (if you haven't already) related to sound issues here -  http://support.creative.com/kb/showarticle.aspx?sid=5764 

Bottom line is I didn't follow all of the steps and learned that 5.1 + sound output is dependent on the material being played back. I am now a happy camper and still impressed by this computer!