I was reading that some iMacs break easy. Do the logic boards or the mother boards burn out on the iMacs easy because thats what people say cause system failure by the logicboard burning out in about 3-4 years and then you have to replace it. Is this true because I plan on getting an when the 2012 versions come out and I am going to be using my Christmas money to get it and I don't want to waste 1,200 dollars.