Recently, my PSU fan started to do an annoying noise, like there is a cable standing in the way of the fan, but it isn't so because the noise doesn't happen all the time. Dust is also excluded because I cleaned the fan myself. It sounds like an electronic buzz or like some screws are loose, immediately after that it sounds like a fridge, and then it comes back to normal, and then it goes on and on.
Also, if I shut down the PC while the sound's happening, the fan doesn't instantly stop, it goes slower, and then the sound is even louder like a car, and sometimes it even speeds down, speeds up and speeds down again until it stops.
What the hell is going on? Could it be the bearings?
Thanks for the answer. Looks like I will get a new one tomorrow, with a better quality hopefully. My power supply cable exploded a few days ago because of a damaged wire, and now I don't want the PSU itself to explode.