Fan is stupidly going fast for no reason.

[Tyee117]

This problem began about 2 weeks ago.
I don't know why but every time I either turn on my PC, or wake it up, the fans speed increases to such a point where it sounds like it's about to explode.

After 30 seconds, the fan dies down to idle speed but it then begins to make a revving noise. No joke; it's like I'm in a car that is in neutral and I'm tapping my foot on the accelerator.

After that phase, the my PC begins to act normal with natural fan speed for the rest of my time on my computer until I put it in sleep and wake it up, or start it up the next day.

 

[xFeaRDom]

Is there any chance you could let me know of the temperatures in idle and on full, or during the times that it happens? That could be a factor.

You could also go into your BIOS and edit the fan speeds to quiet or auto if they're set on something else, or you can set it to manual and ensure that it stays at the same speed at all time, this can be for your CPU too depending on the temperatures.

A third thing is, not sure of your specs of your PC, you can set your boot up process to be slower instead of quick, also known as 'Fast Boot' search it and which version of Windows you have, you can disable it if it is enabled.

 

[m0thersh1p]

The fan speed curve could be off, if you got an Asus board I know it can adjusted inside the Windows with AiSuite. Could be that an update to the software messed with the fan curve.
Also, you're saying it makes noises, have you checked for physical integrity? Could be a loose screw causing the fan to chafe against the block, or a piece of wire/connector hitting the fan.

 

[The Paladin]

This problem began about 2 weeks ago.
I don't know why but every time I either turn on my PC, or wake it up, the fans speed increases to such a point where it sounds like it's about to explode.

After 30 seconds, the fan dies down to idle speed but it then begins to make a revving noise. No joke; it's like I'm in a car that is in neutral and I'm tapping my foot on the accelerator.

After that phase, the my PC begins to act normal with natural fan speed for the rest of my time on my computer until I put it in sleep and wake it up, or start it up the next day.

Asus boards controller doing that. its part of the boot up, spin to max for about 10-15 seconds before the fanspeed controller kicks in to the programmed modes and then the fans works normally...

 

[Paperdoc]

There may be another reason. You've had this machine for a while, right? And this is a new noise.

I suspect the reason is that the fan bearings are starting to wear out. When a computer has been turned off for a while everything cools down, including the bearing sleeves on the fans. If the fan is old the bearings may become worn too large. So, when you first turn it on, the fan shaft rattles around in the loose bearing making a lot of noise, especially at full speed. And that is exactly what the fan does at start-up - it goes full speed for a little while, then slows down because the system is still cool. However, as it warms up, the fan speeds up and makes more noise. But then just running that fan heats up its bearings and they get tighter, so the rattling noise stops. It stays quiet until you shut down and let the fans cool off again.

If that is your real problem source, this is just a warning that it's time to replace the fan before it fails completely.