Thanks for the reply!
My board have the "Zero RPM" option, but when activated it says that is on 0 RPM but the noise continues, when turned off it comes back with the 3000+ RPM...
Using the advanced fan options I changed all the points to the extreme right, like it has to run in 800 RPM even in 80ºC (176ºF), but the RPM doesn't change.
I've tested with different drivers like 21.7.2, 21.8.2 e 22.3.1 but, as expected, same noises. It made me think maybe be the CPU cooler, but in HW Monitor it's running between 1200 - 1800 RPM even when the noise stops sometimes. So I've discarted this option.