[X4U] iMac CPU fan is 3000+ rpm

[Jerry Krinock]

On 2014 Jan 09, at 21:44, Paul Moortgat <paul.moortgat at pandora.be> wrote:

> The WD drive I replace by a Toshiba drive is responsible that the CPU fan of our 2008 iMac is running at more than 3000 rpm.
> That's what iFixit told me it is.

That does not make sense.

> I should have bought the same WD drive.  I'm not sure if these still exist.  It's now more like a vacuum cleaner.  And there's no way to bring down those rpms.

I had this happen on an old Mac Mini once.  The problem was that the person who did the work forgot to reinstall a connector which went to a temperature sensor.  With no temperature sensor, the system defaults to a fail-safe mode, assuming that the computer is hot, and so it turns the fan on full.  You might have the same issue with this iMac.