Filters on fans / vents?

[Pokerfish]

Bit of a newb question here, but I was vacuuming dust out of the inside of my HP Pavilion Elite m9252p today, and noticed how much dust accumulated on the outside of the various vents on the sides of the chasis, not to mention on the inside.

Is it safe to put makeshift "filters" on the outside of these vents to help filter dust?  I'm thinking Swiffers, folded over once at most, and taped to the outside of the chasis over the vents.  Will there still be enough air flow / circulation?  Or will this obstruction lead to overheating?

How about the power supply and system fan slots on the back?

Are there any commercial filters made specifically for this purpose?

Or is it just a bad idea to interfere with airflow in the first place?

Thanks.

[Big_Dave]

You can google PC DUST FILTERS and find a bunch of information.  Swifters would be too restrictive.  It's only the air input that you might use a filter.

Keeping the PC off the carpet is a good idea since a lot of dust is generated due to carpets.

[Pokerfish]

Thanks for the tips.

I guess my next question is: What's the best way to determine the airflow in the computer case?

I did a little test to see if I could determine whether the fans on the back of the case were pulling air in or pushing air out.  I tore off one of those thin plastic "tabs" from a grocery bag and held it up to the fan vents with a pair of tweezers.

Both seemed to be blowing the plastic away from the case, rather than pulling it towards it.  Is it normal for both the PSU and System fans to be blowing air out the back?

If that's the case, then I suppose it's safe to assume that the various vents on the sides of the case (3 total), are designed to be intake vents?  It should be noted that one of these vents seems to align with the internal CPU fan (although the CPU fan is not directly up against the vent).

All the above would be consistent with my finding that there was a lot of dust accumulated on the outside of these vents, yet surprisingly little on the fan vents on the back.

And if that's the case, I guess the sidewall vents are pretty much the places to put filters.

Any insights are appreciated.

[Shawn]

I would not restrict the air flow anywhere on the computer. You are doing the best thing that can be done by cleaning them on a regular basis. Not many people even think of doing that, KUDOS to you for preventive maintenance.

[Big_Dave · Accepted solution]

It's normal for warm air to blow out the back.