Windows 7: ATI HDMI stereo only

I have a gigabyte mobo with onboard Realtek audio AL889A. This machine is used as a Media Center pc connected thru a Yamaha RX-V667. Everything worked great until I had a harddrive crash. Repalced drive and now can only set ATI HDMI audio to stereo. I've seen plenty of threads on this issue but no real solutions. Everything worked great till I installed this harddrive with a clean Windows 7 Ultimate x64. I know this MOBO is capable of 5.1 since that is what I've been using for 3 years. Any help please. THis is driving me CRAZY!!

silly question perhaps...but...did you reload all the mobo and realtek drivers?

Yes. First with the latest drivers, then with the drivers from my MOBO cd. I have tried the latest ATI CCC, 11.9, but have reverted back to 9.12 due to hdmi-dvi when turning tv back on. It's as if Windows can't correctly see the audio chipset.

what is shown in 'Device Manager' for Sound, video and game controllers?

ATI high definition audio
Realtek high definition audio
ATI is the HDMI controller and the Realtek is SPDIF

hmmm...
maybe try this audio codec/driver

Realtek HD Audio Codecs Driver R2.66 - Windows 2000/XP/2003 32/64-bit Download | Realtek

I'll try that tonight. Do you happen to know if the EDID transmits audio info? Can't seem to get a straight answer on that. I also wonder if it's just worth spending $20 and put in a PCI audio. If that would fix it, I get it tonight. This just doesn't make sense!

Realtek showing up here?

No, I haven't any speakers connected. I'm using HDMI to my Yamaha.

The onboard Realtek has nothing to do with the ATI HDMI connection. Also when using HDMI, is the source stereo or 5.1? The HDMI connection will/should only ply 5.1 if the source is 5.1.