i recently got a yamaha rx-v371 home theater receiver, which i wish to use with my PC primarily for gaming and also for watching movies, both in 5.1 surround sound. I have a gigabyte Z68M-d2H in my PC with realtech HD audio manager. right now, its outputting stereo through all 5 speakers (don't have a subwoofer), so both rights output the same and both lefts output the same, and the center comes out all of them. Mobo is connected to the reciever through a toslink cable. Is it possible for me to get real 5.1 surround sound with just what i have here, or do i need a separate sound card etc.