I5-3550 Stock CPU Fan Puzzling Me!

[ammyt]

Hello everyone, I hope I can get some help with this issue over here that I haven't yet found a definite answer to.
This is a very newly built rig, just booted up today, with the following specs:

■GigaByte GA-Z77X-D3H
■Intel Core i5-3550
■Corsair Vengeance Blue 2x4GB 1600
■AMD Radeon HD 7770
■WD Blue Caviar 320GB 5400
■Thermaltake Armor A60 Case
■Seasonc M12SII 650W Modular PSU

Now, the problem lies within the CPU STOCK Cooler's fan. I've always thought that the CPU fan should kick in right when the power switch is pressed, and my friend with an i3-2100 reported that, but this case isn't here. When I turn on my PC, the CPU fan bumps a bit, and tries to push itself like some fraction of degrees, but it then stops, but after the POST beep, it bumps in at full speed and then slows down while spinning.

Is that supposed to happen? Why does it first look like it's trying to spin but failing?
I did not check the display output whether CPU fan error message appears or not as I have no display monitor at the moment sadly... I hope this message is not showing up.

 

[popatim]

My board does something very simular and in the winter my unheated and uncooled computer room is cold enough that the fan stays off long enough to trip the 'failed cpu fan' alarm.

As long as it spins up to full speed under load I would not be concerned.

 

[Proximon]

The fan is stopping because the BIOS is resetting, and so the POST starts over. You will probably need to make a few adjustments in the BIOS once you have a monitor.

 

[ammyt]

My board does something very simular and in the winter my unheated and uncooled computer room is cold enough that the fan stays off long enough to trip the 'failed cpu fan' alarm.

As long as it spins up to full speed under load I would not be concerned.

I hope so, but it really looks like it is bumping and failing at the beginning, I even have not Windows 7 on my HDD yet to load the CPU, just the components and turning them on...

 

[ammyt]

The fan is stopping because the BIOS is resetting, and so the POST starts over. You will probably need to make a few adjustments in the BIOS once you have a monitor.

What kind of changes if you may share please?

 

[ammyt]

Bump...

 

[InvalidError]

Is that supposed to happen? Why does it first look like it's trying to spin but failing?

Probably because the PC powers up with the motherboard's fan controller set to full-power by default then gets reset by the BIOS during POST before the fan gets a chance to start spinning until the BIOS gets around to re-programming the fan controller's parameters after which the fan starts for real.

When I set my BIOS to Quiet profile, my CPU fan sometimes fails to start because the fan PWM output is too low. It eventually spins up after the CPU warms up during Windows boot.

I'm not worried about the fan not spinning since my CPU does not even reach 70C core temperature under load with the fan disconnected.

 

[ammyt]

And the solution to that would be to just leave things as is eyh?

 

[InvalidError]

And the solution to that would be to just leave things as is eyh?

You could set the fan speed profile to Normal instead of Quiet. This should set the minimum PWM duty cycle (if you have a 4-pin fan header) plenty high enough to guarantee fan spin-up regardless of temperature.

If your fan still does not start on its own while idle in the BIOS with profile set to Normal, keep an eye on it while loading Windows/Linux/whatever. If the HSF gets hot but the fan still fails to start, you either have a defective motherboard or fan.

 

[ammyt]

Best answer selected by ammyt.