Thanks for the reply Linda. I found the solution was to reset the SMU. <http://docs.info.apple.com/article.html?artnum=301733> -- Andy Fragen On Thu, Nov 3, 2005, Linda said: >On 11/2/05 9:49 PM, Andy Fragen wrote: > >> After upgrading my G5 iMac revA with 10.4.3 I used applejack to fsck and >> repair permissions. In single user mode I expected the fan to blow full >> throttle but it doesn't stop till the machine sleeps. This has persisted >> through restarts. I saw a note somewhere about setting the processor to >> highest in Energy Saver and I did this. Still the fan is going full >throttle. > >Change the processor to "reduced", rather than "highest" -- "highest" will >make the fan more likely to run. > >If you make a new User on your iMac and log in as that user, does the fan >run like that still? If not, it's a problem in your User account... > >