I have a new iMac which I'm attempting to connect to my Sony KDL-46S5100 LCD Television via HDMI. The TV will not recognize the computer. I have confirmed that my adapter and cable work by testing the connections on a MacBook Pro - that worked fine. However, when I plug the adapter into my iMac the TV says "no signal" and the iMac does not recognize the TV. I went to the Apple store earlier and they were able to get the computer to connect to their TV with no problem. ANY suggestions?
Try connecting it to different HDMI ports (if your TV has more than one). It should be plug&play, although you could see your TV's settings to make sure there isn't anything.
If your tv has PC to select from the menu, us that. If it doesn't, you could have options to change to PC. On my Sony LCD tv, I have to use PC in the menu for it to see my mini.