I have a 17" iMac G5 (iSight) with a 1.9GHz G5 and 512MB of RAM running 10.5.8 with all of the latest security updates. The machine works perfectly fine with the exception of the annoying audible fan noise. From the second I turn the machine on or wake it up from sleep the fans are always at max speed. I've tried resetting the SMU but that didn't change anything and I checked Activity Monitor to see if there was a background process using up a lot of CPU but that wasn't the case. Is there anything else I can do to fix this? I'd rather not re-install the entire OS if it's not guaranteed to fix the issue.