I have a early 2010 15in macbook pro running osx lion. For the past 3 or 4 weeks the fans have been at 3500rpm, despite CPU usage being at 3% and the temperature at 49 Degrees Celcius. They were at these speeds when I was running snow leopard. I have reset the smc, installed and uninstalled smc fan control (that didn't do anything) and done everything I can think of, (I have done hardware checks, disk verification, and the rest) and nothing has worked. Anyone got any advice?