I am looking to use my 50" LG plasma as a second monitor for my computer for movie viewing only, no gaming whatsoever.
my question is: I have 1 open HDMI port available and my GTX 580 has an additional port as it support dual monitors. Now if I buy an HDMI Cable and plug it into my Plasma TV, will the sound from my movies carry over from the file being played on the computer over to the TV speakers or is it going to play from the computer speakers. I've never done this before and I would like to know if what I am doing is the right thing, or is there more of the big picture I am not seeing.
Open the Windows Volume Mixer and you should find "Device" in that window.
Here you can choose the output device for your audio, if there's an option for HDMI you should be able to use your TV speakers through HDMI.
I'm using an AMD card, not an Nvidia card so i'm not 100% sure about it but you could start by checking the Volume Mixer.
You can switch the active sound device in control panel / sound. You should see your onboard and HDMI there. Set the one you want to use as the standard device. Windows supports only one output device at a time for some reason.