Originally Posted by
EndlessWaves
Ah, so you're using analogue now and want to get surround sound?
As mentioned above, either you just need anything with an optical output if you're bitstreaming or DTS Connect/Dolby Digital Live if you need to do transcoding from 5.1 sources that aren't provided in a format your receiver understands over S/PDIF.
Does your Surround Sound system have an HDMI input? If you're only using one monitor then you can use clone mode so it sends video + audio over two HDMI cables.