Last week, I noticed Emily was working behind me on the couch on her laptop. I knew this without turning around because I could hear the constant loud whir of fans going full blast...a sound that could simply be described as "distracting". The sound struck me as odd, as the MacBook Pro has been a pretty quiet machine (except when playing video files). So while she was asleep, I took the laptop into my custody to do a little poking around...A few solutions were discovered in an older thread over at Mac Rumors Forum
1. Go into your print jobs (System Preferences > Printers) and check for any pending print jobs.
2. Cancel any lingering print jobs in the queue.
This is from an anonymous blog poster to Nathan's Pipe: "I had this problem too, but no documents in the printer queue. However, I had recently installed an antivirus program (showing up in my iStat as 'iavd'), and as soon as I turned that off, the fan slowed to a stop!"
Repair Permissions (Applications>Utilities>Disk Utility)
Strangely the problem was DashboardClient. under the "%CPU" it says over 76% so i just quit it and then my fan slows down to a normal rate (about 3500 rpm).
I didn't discover any extraneous print jobs in the queue, but I did find a few unnecessary printer profiles and added smcFanControl 2.3 to tweak when and how fast the fans would come on (the utility also gives you real-time feedback about how hot your CPU is running for before and after monitoring). Also using Activity Monitor (found in your Applications>Utilities) I was able to hunt down and kill some extraneous processes which may have added to the fanfare.
After following all of these steps and restarting the laptop, the fans were quiet, the laptop was operating well within normal operating temperatures, and I covertly returned her laptop to her desk as she slept, good as new.
Image by Christoph Bauer