CPU fan error, please help!

If the fan is working check the BIOS to see what it says about fan speeds. When I set up my new build I had a similar problem. Turns out the fan was spinning at a lower RPM than the lower limit in the BIOS. All I had to do was change the RPM limit and the message went away.

make sure the cpu fan on the right header and that you did not miss any of the pins.

I double checked the conection of the cou fan with the MOBO manual and its connected to the right header and did not miss any pins.
@aleatoire could you elaborate a bit more about that? You suggets its just a limit issue? I'll try lowering the rpm limit on the BIOS since today i got my keynoard lol  

I'm not entirely sure that what happened to me will apply in your case however I'll try to elaborate on what happened to me.
I recently set up a new build with a Hyper 212+ CPU cooler. Sometimes on start up it would pop up with a "CPU Fan Error!" message in the POST. I could see that the fan was still spinning fine so I went into the BIOS and under a tab (I can't remember what one), there were a whole bunch of different fan settings and speeds. The RPM count listed under 'CPU fan' was highlighted red. Below it was an option to select at what minimum RPM the POST would give the "CPU Fan Error!" message. As it turned out the idle RPM of my Hyper 212+ was lower than the RPM set in the option mentioned above. I could just select an RPM that was lower than the idle speed of my Hyper 212+ fan, but high enough that I would know if it had stopped functioning properly.

That may not help in your case, but if you can see the fan spinning then it's worthwhile checking. Good luck.

I had the same issue as the OP, and this is exactly what the issue was.




At least on my MB (Asus Z77), if you have the fan installed on say the CPU_OPT header instead of the CPU_FAN header, the error message is that no CPU fan is detected. I think it has to be on the right header to show this particular error.

I checked the bios and it is somewhat what youre describing. The bios shows that the cou fan is soinning in red numbers at about 580rpms with a cpu temp of +18C is that temp okay?

18C is a VERY low temp for a CPU. In normal operation it is usually much higher, but exactly what is normal depends on which CPU you have. So look for info on "normal" operating temp for your CPU. That 18C may be just at start-up if your room is cool, but it certainly should rise higher than that within less than a minute.

I did some twitching here and there and the problem was actually the fan running at fewer roms than the minimun set by the mobo. Tested the cpu and it was at normal temps. Thank you for your answers  

Best answer selected by Pinwi.