It looks like my friend may need to replace the hard drive in his 20" (white) C2D iMac from 2006. Does anyone know if the power draw for current 1TB or 2TB drives exceeds the ability of the iMac to provide sufficient power? I would not mind using an Eco/Green Drive for heat/power draw reasons as long as it is at least as fast as the stock 7200 RPM originally came with his iMac. (I'm not sure whether the newer 1TB eco-drives would be just as fast because of the newer designs of the drives.) Thanks for the suggestions.