No CPU Fan Installed

[MKNork]

What could be the cause of this message being shown at start up?
I recently changed the fan on my wifes PC,Packard Bell,because the original had died,very slowly.
I couldn't replace the heatsink (which was blocked with dust) as it has some strange kind of contraption on the motherboard.
All connections etc have been thoroughly examined and checked.
Could it be that I have to replace the motherboard?

 

[derrycraig]

Its probably the fan connector, the fan connector on the motherboard has three pins two for power and one for the sensor, which measures fan speed, some fans don't have this connector for the third pin or it could be a bad connection, eitherway the lack of data from the fan is probably causing this message, thats assuming the fan is spinning and appears to be working OK.

 

[MKNork]

Thanks derrycraig
Yes the fan is spinning.I had assumed it was to do with the connector as everything else was ruled out during my visual checks.Hense the question,do I need to replace the motherboard

 

[Mirob]

In most BIOS you can select "stop on no errors" or similar and this kind of message will go away.