Sorry for the delay in game. This having to work for a living is the pits, should have been born rich. Maybe next time.
In answer to your question, the machine diagnosed itself. The screen went goofy then half disappeared so I ran diagnostics. That showed the graphics chip well over temperature spec. When I investigated the problem it turns out Apple had a bunch of problems with that chip. I don't know whether it was a faulty chip or inadequate heat removal or maybe even the plastic case not dumping enough heat. What I do know is that it was only a few months out of warranty and they would not address the problem unless the extended warranty was purchased at the time of sale. The only fix at the time was to replace the mother board to the tune of $800. As I said, I was real unhappy. That was my fourth mac and I had never had a problem. Not standing behind your product, within reason, is a real good way to lose customers. Like me.
Wow, must be having a senior moment. Just checked a post from 09 where I was asking for info about the display problem. Guess it was more than a few months out of warranty. Still, they knew they had a problem and the machine was registered. In my view, had they let me know I might have a problem, we could have worked something out. No, they held their corporate breath and took the low road on anyone with a problem out of warranty.
Who knows who won. I was probably responsible for a couple dozen mac sales over the years. Course, I told just as many people about my problem so maybe I cost them a bundle too.