Little question about SPDIF output

[LucasALC]

hey all, and sorry if this is the wrong forum to post this, but I think there will be many people here that know about this.

I currently own a Leadtek soundcard with a CM8738 chipset (analog/spdif output), and I want to get a decoder/amplifier (I now have 4 speakers connected to the analog outs) to get much better sound quality and all... I've quite clear how the system works, except for one thing, what would happen if I wanted to play some mp3s with Winamp, those 5.1 oggs or play some games? would the spdif out just won't work? would it downsample (in the case it's 5.1ogg, for example) to pcm 2ch? I have NO idea, so please give me a hand with this :)

cya!

[Slogra]

Mp3s will be decoded by your pc and send as PCM through the cable. So your receiver won't have any trouble playing them.
I don't think 5.1 ogg will work, you'll probably only hear the two front channels through the digital connection. The only digital multichannel formats supported by receivers are Dolby Digital or DTS.
BUT most of receivers also have analog multichannel input so you can connect your analog multichannel output of your soundcard to this.
This way 5.1 ogg will work, it's just not send digitally to your receiver (just like your 4 speakers work now). Same for games.

Summary :D :
If the signal isn't Dolby Digital or DTS, your computer will decode the sound to PCM and will send only the 2 front channels through the digital connection.

[LucasALC]

that's just what I wanted to know! very good explanation too :D thanks!