My iMac 5,1 late 2006 (from 26th of June 2007) is crashed (not kernel panic) & blowing the CPU fan very fast for the five times. Then it begin suddenly ticking (6th March 2009).
I called Apple ask for a repair... they said wait untill it's broke.
Then I called a second time that i'm claiming on the laws in my country. That I can expect if you buy a Mac for 1900 euros that it is normaly working for at least 21 months.
Oke they said go to a Apple Sevice Provider and let them take a look.
They said the couldn't find or hear anything. 85 euro gone.
After sending a signed letter Apple called and said go to
the second Apple Service Provider but said the same thing.
But maybe you do hear the tick? It drives me nuts!
Now the ticking comes more frequently.