I am not certain whether to post here or not but I figure it might be worth a shot, if not please direct me to where I might get an answer...

I just upgraded my PC and bought a new Yamaha receiver to go with it...
I now have an AMD64 sitting on a gigabyte K8nPro MB and now for my issue:

I have digital SPDIF (by way of fiberoptic cable) out on the board and an input on the above mentioned yamaha model however I can not get true surround sound unless I use prologic which is just a 2-channel converted to surround.

I flipped through the manual and it says something about a signal over 48kHz is read as only 2 channel, I can not find what the board puts out to see if this is the issue.

Also, might be a setting on the PC or an issue with nForce3, anyone have any ideas I can try?

thanks much!

So your Yamaha has onboard Dolby Digital and dts decoding?

SPDIF-out from any current digital solution save the NForce 2 (with the MCP-T implemented fully and dolby digital encoding turned on in surround apps) will always be in stereo except in the case of preencoded surround content, like a dolby digital or dts encoded DVD.

Have you tried playing DVDs with the optical output and the player set to digital out?

Incidentally, it is almost a certainty that the optical output is not carrying anything over 48KHz