If you would have told me one year ago that adding a pet to the house (that doesn't shed and doesn't even stay in the same room as the computer) could add so much dust that I am now having to dust the innards of my PC once every two months... I'd call you crazy. But, it wasn't until I noticed Fallen Enchantress screwing up on me (graphics stuttering badly), I pulled open the case after I deduced it was not asoftware error, that I noticed a cake of dust on my GPU fan. Man alive! So, last time I dusted I kept thinking, 'Wow, won't have to do this for a another several months." Nope... I was wrong. So, now I am thinking I'll have to take other measures. Change the vent screens around the house more often, clean more often, maybe buy a dust/allergen remover. I have heard people suggest putting pantyhose around the vent holes on the PC, but that ain't gonna help much, at least it won't help this machine.
Sorry for the rant... anyone want a small dog? I've taught it to sit and shake hands. Now all I need to do is teach it how to dust itself.