You are sad.
@everyone else
Rubber gaskets fitted to fans, a.k.a. vibration dampeners or rubber fan mounts, either reduce or completely eliminate vibration from being transmitted from the fan to the casing panels. The casing panel - a flat piece of metal - picks up vibrations and behaves more or less like a loudspeaker cone.
Tightening the screws on a vibe damper too tight will eliminate the effects of vibe dampers, leaving it too loose will make things even worse. Also, great care has to be taken in installation of one of these things.
Basically, for vibration dampers to work, don't screw up on installation.