G750JZ Left fan issues

[Honami]

Hello,
Since this morning, i noticed strange noise from my left fan (probably cpu fan).
I hear sometimes very strange noise, like something is stuck inside the fan.
I checked the fan and nothing is stuck inside.
Also sometimes the fan stops working at all.
If i enable the gpu oc and the fan is at max speed, the fan works fine.

The fan does not have any visual demage from what i saw.

Any ideas how to debug this issue without trying to replace the whole unit?

[navis995]

How sure are you it's something wrong with the fan?
If there's nothing stuck and there are no visual damages visible there maybe nothing wrong with it.
It also may be your HDD producing weird noises.

Could you try and elaborate more about the "sound"?