Its just regular drywall. He is getting the very last tip of a connection signal showing at the top. I actually think its just something wrong with his iMac. I have the same iMac G5 and his runs REALLY loud and has had a few other problems. His iMovie isn't working right either and the fan noise is almost unbearable. I think he is just going to take it back and exchange it. Thanks for all the help though and hopefully this new one will work better for him.