Can't get the TV to work.It has the inputs but says invalid format when in RGB (PC)

What cables are you using to connect the laptop to the TV? It should be one of four cables... VGA, DVI, HDMI, or S-Video. If it is not one of these cables... that is most likely the problem. Your computer must also have a Video-out connected internally (for example... my laptop has S-Video out... but it isn't hooked up inside the computer... the port is there.. but it is useless - an option on my laptop I guess). So let me know what cables it is... what type of laptop... and what brand of TV. I can probably figure it out if I have more info. Cheers!