This is what is on the specs of the card.
Integrated HD audio controller
Output protected high bit rate 7.1 channel surround sound over HDMI with no additional cables required
Supports AC-3, AAC, Dolby TrueHD and DTS Master Audio formats
The strange thing is that last night I was playing Dead Island and I had sound coming out all of my speakers but it was late and I couldn't test and see if the sound was different between the rear and side or if it was just repeating the same sounds out of both.