Why can't my computer connect to my HD tv?

My tv is HD. It is a LG LCD 32" 1080p tv. When i turn the resolution on my computer to the recommended setting, the tv goes black. I have to keep the setting at 1280 x 1024 in order to see the screen. My video card on my computer is a galaxy gts 450. Anyone have any ideas how i can turn the resolution on to 1920 x 1080 without the screen blacking out?