I wasn't sure if I should post this in Home Theater Computers or Video Processors.
I know that the GTX 560 TI supports 7.1 surround sound, but I can't get it to work. I have the latest Nvidia 280.26 drivers installed. When I go into Control Panel > Hardware and Sound > Sound, I have four playback devices available: LG-TV1 (HDMI connection from the 560 to the TV); Speakers (which I have my Turtle Beach 7.1 headphones connected to); Realtek Digital Output (for digital coax S/PDIF connections); and Realtek Digital Output Optical (for optical S/PDIF connections). If I right-click on LG-TV1 and select Configure Speakers, it allows me to select Stereo - nothing else (see first image below). If I select Configure Speakers when right-clicking on Speakers then I have the option of Stereo, Quadrophonic, 5.1 Surround, and 7.1 Surround (see second image below).
The way I have my PC set up is with an HDMI cable from my PC to my TV, and then a digital coax from the TV to my Onkyo receiver. Pretty straight forward, or so I thought. I can get stereo output with this configuration, but nothing more. I tried to change the default Sound output to Speakers but I can't get any sound to come through (perhaps this option is to be used with the HDMI port in the motherboard?). I connected an optical TOSlink cable to the S/PDIF port on the motherboard and connected it directly to my receiver, but I'm not getting any sound that way either (perhaps the HDMI connection from the 560 is disabling the S/PDIF connection?). I then connected HDMI from the 560 to the receiver directly, then another HDMI out from the receiver to the TV; still, no audio. I even connected DVI from the PC to HDMI on the TV, just in case the HDMI from the GPU was cancelling the optical out; of course, that didn't work either. So far, the ONLY way to get audio is with HDMI from the 560 to the TV, then digital coax to the receiver, but being limited to stereo is less than satisfactory.
FWIW, this is a brand new PC build. I made a gaming HTPC with the Galaxy GTX 560 TI, i7 2600, DH67GD Intel motherboard, 8GB RAM, etc. My old PC had a 9800 GT so I used DVI to HDMI for video, and digital coax from the motherboard to the receiver. I much prefer digital coax over TOSlink just because the latter always seems to fall out so easily. Alas, my H67 mobo doesn't have digital coax S/PDIF so I'm trying to make the most of what I have.
What am I doing wrong? Why don't I have more speaker configurations available with the 560's HDMI connection? Is HDMI from the 560 blocking the optical S/PDIF connection?