Question Fan noise apparently caused by rattling against case?

mattdp

Distinguished
Apr 14, 2005
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I've had a Dell Inspiron 17 5770 for a couple of years now. Right after it was out of warranty, it developed a loud fan noise fault. It also felt like it was running slower than normal. I put up with for a while but in the end, it got so annoying that I opened up the case to clean it out, expecting to find a big lump of dust or grit in the fan.

There was neither. What surprised me was that when I blew in or turned the fan manually there was no sound at all, not a whisper. Not does the fan seem to wobble inside the case. I unscrewed the fan from its moorings to clean underneath and while it was still connected but unmounted, I powered up the laptop to see what would happen. To my surprise there was very little noise from the fan: the noise only seemed to start when I tried to put it back into place. It was like the whole fan housing was rattling against the laptop casing.

The only thing I could think of to do was to screw it back in, tighter. But that's done nothing.

So the problem certainly isn't dust. I've never heard a fan with a faulty bearing but since I can spin it manually without it making a sound I presume it's not that, either, so replacing the fan won't do any good. That said, I don't know why vibration noise would have an effect on performance. Has anyone come across a similar problem or have a possible fix I can try?
 

Lutfij

Titan
Moderator
There was neither.
I had the same thing happen to an Acer laptop I was given to by a friend of mine to work on. The fan was squealing badly even at low RPM's. I eventually had to replace the fan entirely, after getting a replacement unit off of Amazon.