GeForce GTS 250 SPDIF for HDMI

Hello guys!
I'm new here in community, and I think that you guys can help me with a problem before I do something stupid hehe
Well, recently I've got a new TV that have HDMI connection, and the first thing I did is conect my PC by the HDMI connection (using DVI to HDMI adaptor). When I connect the HDMI cable to TV, the sound is disabled. I think that is because HDMI connection make default the audio of graphic card... but nvidia cards don't have integrated audio in the card like ATI, and doing one little research I figured out that all cards of serie 9xxx or newer has one SPDIF in to receive the audio and pass to HDMI cable. Here is the part that I need the help of you guys, in the card I see the two pins for SPDIF, but in the motherboard the SPDIF OUT is 3 pin (one 5v, one gnd and one positive)... what pins I use to do this connection? Someone here already do this ?
Thanks (Sorry if my english is bad, I know that i need to improve.. but I don't use google translator!! rsrsrs)

And I have the same problem, the cable of graphic card has 2 holes and mothetboard has 3 connectors and I do not know where to put the cord. I have evga GTX 260 graphics and ASUS P5Q TURBO motherboard.

the 2 pin white connector plugs into your card
the other end usually has two split connectors, the black one (labeled BK) goes into the GND (ground) pin. The other one is sometimes orange (OG) and goes into your SPDIF labeled pin, most likely your positive pin but check your mobo manual.