don't know where to put it, but just receive a email from NCIX
they have now 5670
NCIX.com - The new ATI Radeon HD 5670 graphics cards
they have now 5670
NCIX.com - The new ATI Radeon HD 5670 graphics cards
I would imagine it would support audio over HDMI since the 5970,58xx,57xx models support it as well as the 48xx series did as well.
basically what this means is that the sound is passed through the PCI-E lanes, just like how the 4000 series did it.Link to specs for 5670: Here
"Integrated HD audio controller:
Output protected high bit rate 7.1 channel surround sound over HDMI with no additional cables required"
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