Dear Quincey

Dear Quincey,
you are my last hope! I own macs since 9 years - first this cute
strawberry colored Imac G3 and now an iMac G5 1,8 GHz since 2 years.
I wouldn't change for a PC, no way!
But my iMac G5 drives me crazy with its loud fan noise and despite
going through almost all available support and chat websites about
this problem, I was not able to find a solution, even if obviously a
lot of iMac G5 owners have the same questions. Do you have any ideas
how to get rid of this annoying noise? I tried to contact Apple
support, but they only answer you if you pay a (not so small) fee for
the support if you don't have this Apple insurance.
I would appreciate your answer and thank you for your time.
Marlene Fodor
Tucson, AZ
After installing 10.4.3, I was dismayed to find that it had sent my G5 (a first-generation Dual 2.0GHz model) into the land of eternally cycling fans. Every few minutes, for seemingly no reason at all, the fan noise would ramp to near-max for a few seconds, then spool back down to idle. Watching with top, there was seemingly no cause for this activity -- no process was sucking up the CPUs, and everything looked completely normal. Needless to say, this was extremely irritating -- if you've ever heard a G5's fans at maximum speed, you know how loud they can be. It was so annoying I was contemplating downgrading to 10.4.2, just to get things back to a quieter noise level. I tried the basics -- a simple restart, a SMU reset, and a PRAM/NVRAM reset. None did the trick. Then a friend pointed me to another possible solution he found at MacFixIt, involving (of all things) the Energy Saver preferences. Open the Energy Saver System Preferences panel, and click the Options tab. Click the Processor Performance pop-up menu, and set it to either Highest or Lowest -- anything other than Automatic. Close the panel, and you're done. Not wanting to give up any performance, I set mine to Highest. I made this change on Friday afternoon, and since then, the fans have returned to their pre-upgrade behavior. They now only get slightly louder when I do something CPU intensive, and are at the same nice-and-quiet level the rest of the time.
HungrySeacow
10-01-2006, 12:13 PM
This maybe a long shot, but try taking it apart and using an air can to blow out all the dust in the air ducts. Perhaps there is some sort of blockage causing some of the sensors to request high fan speeds.
lanturlu
10-02-2006, 04:26 AM
Thanks for the suggestion HungrySeacow, I tried it yesterday with a vaccum cleaner. Although there was not so much visible dust, it seems to have made a difference. I've been running 10 applications at the same time with fan speed <2000 rpm... let's hope it stays like that forever!Sometimes the simple solutions are the only working ones!
01-06-2006, 08:01 PM
Hi everyoneJust sat at my desk surfing on the imac and suddenly realising that the fans are running loud. In fact when I think about it they have been getting louder over the last 8 weeks or so!Checked the cpu temp and it was 58 degrees C, not really that high. Then I started to panic thinking I may have faulty fans. Checked the top vent at the back and there was some airflow especially on the right hand side. Then checked the bottom vent for airflow there was some but not a lot.Then for some reason I decided to run my fingers along the face of the lower vent.UUURGGHH!! I can't believe how much dust and crap fell on to my hand. I quickly wiped round the whole surface. Almost immediatley the fans started to slow down. Fans took about 2 minutes to settle down. WOW I'd forgotten how quiet these machines can be.Only thing now is, I can faintly hear the hum of the power supply!!So if anyone gets loud fan noise on their Imac G5, just give the lower air grill a wipe and see if that cures it.