Dust preoccupation

i got a brand new computer. it is awesome. it has cool lights and a lot of fans. its my bebe.

i heard that dust is bad for computers, it makes them warmer and shorten it life duration.

as soon as i herd that i cleaned my whole room away from the dust. one week after i bought it, i look inside the case's window and i see a fine mist of dust covering the insides of my computer. it is really thin tho, you cant see it without strong light.

so..
1. is it true if i put pantyhose over the draw-in fans there will be no dust coming in my computer?
2. if yes, then how do i make the pantyhose stay in place? is rubber tape o.k.?
3. am i worrying too much or i really need to use the dust-off now?

i do not think you know what preoccupation means, therefore, i cant answe whatever question you are asking.

I use some pantyhose on my intake fans. After a month or so they have a layer of dust that I vacuum off so they definitely do stop some dust. I still get dust in my case and clean it about once a year though. I removed my fans, chopped the pantyhose into a square then stretched it over the fan assembly and kept it in place with an elastic band. Afterwards I screwed the fan back in place on my case driving the screws through the pantyhose to keep it in place allowing me to remove the elastic bands.

The dust is inevitable since all homes and offices are dusty to the degree where a computer just accumulates it by virtue of airflow AND electrostatics.  (The electrostatics is why TVs get so fucking dusty so quickly.)

>>3 has a good idea for limiting the size of dust that can enter your case from the airflow, but you have to be sure the fans suck air IN through their throats.  Some fans expel, which sucks air in through various other vents in the case.  Also, putting any filter on an airflow will slow it down, so make sure placing such filters won't reduce the airflow too much, which will just cause your case internal temperature to rise anyway.  Some systems are fairly poorly designed in that the fans barely keep up with the heat inside the case, so further reductions of airflow will push the system over the edge into overheating.

Get a Dyson. It has cyclones that spin dirt out of the air so there's no need for filters that can become clogged and lose suction.