I just got my late 2012 iMac yesterday. i7, 3tb fusion, 24gb RAM, 680MX After about a 6 hour migration of around 650gb of info I ran it through its paces. It works great and is much speedier. However, I believe the hard drive is the culprit in the coffee machine noises. My late 09 iMac would do it when it was transferring data for time machine, but then it was whisper quiet. I've ran it idle for about an hour and it won't shut up. Is anyone else experiencing this?