Price / performance good, but vibrates with screw mounting quite strong

I run two of these fans at the front air intake of my PC case, where they replaced a "standard fan" of Corsair. Under full load, although they are already audible, but by the PWM function, this should probably occur only rarely in practice. The fans run in my section with 600 rpm. More than a minimal air noise is not immediately perceptible. The processing is very high. The optics must each course itself liked me personally the black / red color contrast, however, says very. Not too cheesy, but still noticeable. Can be used without problems even in discreetly held PC cases.

In my PC I also have a 120 mm model of Wingboosts which is mounted using the supplied rubber bumpers. Here there is absolutely nothing to complain about. Two additional 140mm models in my PC but I had to fix for reasons of space unfortunately conventionally with screws and here show the fan unfortunately their weakness. If you screw them namely rigidly to the housing, render a soft, but in the long run clearly audible, nagelndes noise on the housing frame. I have become almost mad in search of the origin of this noise, I could not at first imagine that it comes from the fans. I had already broken half the PC and in the meantime buy an anti-vibration frame for the hard drive, until I then noticed by chance that the sound will disappear when the fans are disconnected.

Conclusion: Who has the power to fix the fan with the supplied rubber buffers, can safely access (I'm going to my 120mm Wing Boost 2 also reserve) who must, however, screw tight the fan / want, should better leave it alone. My two 140 mm fans are the days by Silent Wings 2 of "be quiet!" replaced. Let's see if that works better with the supplied "pushpins" for mounting. This should be supposedly suitable for my space, so I can do without screws. Let's hope the best ...