I have a flat screen TV in particular model #lg 42lv4400. I have it setup via HDMI to my computer. In the TV I only have two options 4:3 and 16:9. When I setup the TV to 16:9 I get the left side of my screen cut off. Basically the clock in the bottom corner is off the screen. On the other side I see about two inches of black. I'm assuming the black is the same amount of space that is being cut off from the other side. I have tried going into the Nvidia control area and moving the screen to the left. The problem is as the screen moves left the right side does not fill in the empty black area but instead starts to disappear. I'm not sure what my options are to fix this? It is very frustrating because a huge chunk of screen on my desktop is missing. Please if anyone has some idea on how to fix this I here to try!
A bit more detail if necessary about the setup. This is a virtual pinball setup. So, the full setup to the computer is the following:
42" lg tv into one video card (gtx 570) this is the one being cut off
another video card (gt 440) is controlling a 17" monitor (pinball dot matrix display) & 27" tv (the pinball backglass
The OS is windows 7 and in the display settings area the setup is as follows:
  
 is 42" tv
 is 27"tv
 is 17" monitor
I have tried increasing the resolution past 1900x1200 to see if I can force it larger to fill that area but it does not work. I also tried scaling which also did not work.
I suspected maybe having two Nvidia cards running at same time might be the issue,. That be the next thing to do is pull one of the cards out. I'd rather not do this until I get confirmation this may be the issue due to it possibly messing up some configurations I have for the software that runs the pinball emulation.
You could try using different video cables. In the past I have had the same issues with the black bars on the screen, and the Nvidia panel didn't help either. I solved the problem by using DVI cables instead of HDMI/ VGA. Try using different types of video interfaces if your TV supports them. Otherwise it may be the fact that you have separate cards running at the same time, as you mentioned. If this is the case, you might want to consider selling the cards and purchasing one that supports 3 displays at once. For example, Gtx 600 series or pretty much any newer AMD card. It depends how much performance your setup requires. I have honestly never even heard of a setup like this, I would not know.