How to have a TV monitor show in display settings?

I have an M17x Alienware, 280M SLI GPU. I just recently bought an HDMI cable and have tried on two different TV's to do dual monitors. I used a VGA cable before and it worked perfectly fine, both monitors (my Laptop one and my Samsung TV) showed up in Windows Vista's Display settings as - accordingly so - Display 1 %26amp; Display 2. But this was with VGA, now that I'm trying HDMI, I dont even have the option to select another monitor in Display Settings. I also went into NVIDIA control panel and the only option in ';Set up Multiple Displays'; is ';Only use one display (Single).'; I can, however, make my screen laptop appear on the TV monitor by changing the Display in the submenu to ';Samsung'; but that is the only way and when I do that, my laptop screen goes black. I want BOTH screens to work, but it seems that in both Nvidia Control Panel and Display Settings, I do not have the option to do so.

Can anyone help?

Yes, I do have the latest drivers.

Thank you,How to have a TV monitor show in display settings?
Try booting with the TV turned on. It's a shot in the dark, but worth a try. Oh and don't use Vista's display control for anything that nVidia's control panel can do.