Sony Vaio cannot connect to HDTV

[DC328is]

Hi, I have a Sony lap top and i wish to connect it to a Samsung HDTV via PC monitor cable.

but for some reason it will not read the signal.

i tried swapping with an HP lap top and it was okay.

Anyone have suggestions?

Thanks in advance!

[roopi]

What model of Vaio? What model of TV? My guess is the resolution settings.

[eblend]

did you press the function key + monitor select key to allow external port to send signal?