System fan runs at high speed continuously

**Sukhvinder** · 22-01-2009

Hi Friends,

My computer does not have the above problem before but this problem has arises suddenly and has no clue about how this has happened.

when I leave my computer unattended for a couple of hours the internal fan is running at high speed,i only understand that when the computer has some simultaneous work to do this time only CPU workload increases hence the internal temperature and to maintain proper temperature CPU fans runs faster,but this thing has not seems anywhere still my system fans runs at very high speed.

Can any one suggest how should I get rid of this problem.

Thanks in Advance!

**Arkad** · 22-01-2009

I completely understand the frustration that you are currently expericing. But first in order for me to help you resolve your issue I need to know what model iMac G5 you have.

**Willard21** · 22-01-2009

Actually, I could see that fan behavior as very indicative of a temp issue if what you are describing is the fans ramping up to full shortly after turning on. So what did temp monitor report?

**Myron** · 22-01-2009

Sensors immediately after powering on read as follows:
Graphics 25.8 degrees c
Power supply 21.8 degrees c
HDD 19 degrees c.

I have reset pram, pmu & nvram and updated OS X via software update to 10.3.9. I am going to try one more thing & that is to do a fresh install of OS X 10.4 as the ibook currently has a swapped out hard drive from another ibook.

THANKS