Thanks for the replies.
COLGeek: Tried that, and various rebooting combinations but of course when I reboot the screen is blank!
x Heavy: You're saying the integrated graphics card hdmi doesnt work? So I need to install a new graphics card? If that's true, I'll take it back to the store but how can I be certain its that?
Make sure that when you are connected via HDMI that you set the HDTV's input to HDMI. Same goes for VGA. Most HDTVs will not automatically change from one input device to another.