HI, Just installed a 1.5 TB WD Caviar Black hard drive in my early 2008 24" 2.8 ghz imac with 4 mb ram. The temperature reading via istat pro and Temperature monitor reads a consistent 60 degrees Celsius. This is with light activity and the cooling fan running at 1600 rpm. It is hot today, 78 degrees Fahrenheit in my house. Should I be concerned ? Thanks.