So I have a mid 2010 Intel imac with fan issues. I just replaced the HD and installed Lion, shorty after the install once I was getting acclimated with the new interface my CPU, HDD and Optical drive fans started running at full blast. I did some investigating and found out that replacing the HD may result in an increased fan speed, but not sure why the other two fans are running at high. I have istat and the temperatures are normal just not the fans. Does anyone have the same issue and or can anyone help?