Hmm, so I have another tip: if you want to clean your PC with the fan, you would be well advised to do it outside. Because I don't want to spread all that dust in the flat. I could well imagine doing it on the balcony, as I already do when I blow through my NAS. Not everything comes out, but it works for the worst even with a full lung (first take a deep breath and then blow hard, pause before repeating because all the dust has to evaporate first).