I just received my new iMac (17" 2Ghz) and I love it...but I have a question about the fans. The fans make a low-level grinding noise (best way I can describe it). It isn't irritating, but it IS audible even at its lowest level without putting my ear right to it. What concerns me more though is that the fans ramp up when almost any application other than Mail or Safari is loaded. For example, when I load up iTunes, the fans almost immediately ramp up - at which point they are VERY audible. After about a minute they quieten down again. The room the iMac is in is very cool - a basement - and near an A/C vent, so ambient temperature is not an issue.