Hi, Warlock. As to the fan blades, not a dumb question at all. imho. Air from the Inside, outside, probably doesn't matter, the objective is to get the fan clean, eh? ![:)]()
For a 3rd option, I don't use air for that at all.
Instead I brush them off with a half inch round natural bristle brush while catching any dislodged dust with a vacuum.
If you do use air, don't let the blades spin freely, hold them with a brush or something that won't break them.
Also, using things like alcohol or household cleaning fluids to get them squeaky clean can cause the plastic to become brittle.
There is a previous post on here about this, may help:
http://forum.piriform.com/index.php?showtopic=26843
I thought of these points later:
- Be careful with compressed air. Anything you spray with it can get really cold, sometimes to freezing. Its
possible to get the part cold enough to destroy it. Also, once a part has been cooled, water may condense on it,
and that can cause a host of other problems. So hold the nozzle back a bit from whatever you're dusting.
- Just hold the vacuum cleaner hose inlet inside the case so that it pulls out any dust you dislodge. Don't touch
any components of the computer with it.
- Don't use any cleaning fluids inside the case. If there is something you can't remove with air, a brush and a
vacuum, just leave it.
- Don't remove the processor or the processor cooling fans unless you must. If you must remove the processor you'll
need to replace the thermal paste when you put it back. Find out which thermal paste your manufacturer recommends
and get some before you start. Follow the mfg recommendations, even if your warranty ran out long ago, as mine
has.
Also a ton of information available via google:
http://www.google.com/#bav=on.2,or.&fp=ce04e5747f6b57cf&q=how+to+clean+inside+the+computer+for+dust