Let Sleeping Dust Lie
SHA Newsletter: Vol 1. No. 9

Let Sleeping Dust Lie

If you have ever had to open your PC up, this article is for you. What should you do about all the dust inside the case?

Whenever your system runs, it pulls room air through the system enclosure, and that means that dust, dirt, pet hair, smoke, and all the rest comes along for the ride. Is it a good idea to clean all that dust out before you close up? Yes, and no. Here are the things I think about when I'm faced with dust bunnies inside a computer.

Be Smart Before You Start

Before I open up a computer, I study up on it a bit. You can find out about your system from the owner's manual or the vendor's Web site. The computer vendor's information will tell you how to open things up and what parts are safe for you to work on. If you are not completely confident of your ability, don't open the case, and get help from a technician who knows.

There are many parts in a modern computer that cannot be opened, disassembled, or removed. Others, such as CPU chips, can be removed, but only using special procedures.

Around the Case

If you can see dust on the case or around openings, clean it off. Dust that gathers here keeps cooling air from getting inside.

On Connectors

Before I attach a cable to a connector covered in dust, I blow the dust out. The same goes for a “slot” inside the computer where I want to install a new circuit board. Dust here will do no good, and a quick dust-off will prevent a dust-up of trouble when something fails to work.

On circuit cards inside

If you have a circuit board in your computer that is dusty, and you aren't trying to fix it, then leave it alone. Removing dust from the surface of a circuit board, or printed wiring board, is asking for trouble.

On heat sinks around the CPU

In most modern PC's you won't find dust around the CPU and its heat sink. That's a big block of metal, usually aluminum, with an array of fins on it. Heat from the CPU chip warms up the aluminum heat sink, and a small fan brings in fresh air to cool things off. The moving air around the heat sink keeps things clear.

Leave this area alone. Between the heat sink and the CPU is a layer of special paste that helps remove heat by making sure there is a solid connection from the CPU chip to the heat sink. If that layer of paste chips or cracks, then the CPU can overheat and be ruined. You can't see any cracking even if you go looking for it. Damage around the CPU like this is a stealthy computer-killer.

On a Keyboard

It's OK to blow dust off a keyboard. Make sure you blow off the dust across the keyboard so you don’t drive dust deep into the works. You may find, however, that dirt and stains are more common problems for you. Avoid eating at the computer. While it's easy to get rid of a little dust, liquids, pet hair, and crumbs can be difficult to clean. These might require that you disassemble the keyboard. The best way to recover from spilling a cup of coffee or a soft drink into the keys is to replace the keyboard.

How To Blow Dust

I use a “canned air” product, formally called a compressed gas duster. “Canned air” is actually a gas propellant under pressure. It creates a clean, dry, fast stream that clears dust away. Since it's flammable, you want to use it sparingly, and only where there's plenty of ventilation. You should not inhale it or try to concentrate it. These should come with a fine tube for directing the spray where you need it. These products work without exposing your computer to moisture or oils. That's why they are preferable to air pumps or compressors for cleaning things up. Read the directions on the can for how to use them.

Never blow on parts of your computer to remove dust. The canned air product will blow faster than you can, and it will keep you from getting a face-full of dust!

Why Not Blow Off the Circuit Cards?

The gas in the duster can is under pressure. When it comes out, the expanding gas cools off rapidly. If you blow too much, frost will form on the can, and it will be too cold to handle. That sudden blast of cold can cause the connections on a circuit board to crack and can cause a chip or component on the board to fail. In fact, troubleshooters will sometimes blast a component with this cold gas because the rapid change in temperature can help them identify weak parts.

Blasting the circuits with cold air just to keep things tidy can actually cause parts to fail. On the other hand, a little dust on the board usually causes no trouble at all.

So let sleeping dust lie.

Please note: Any trademarks and trade names of others mentioned in this message are the property of their owners, and not Stoney Hill Associates, LLC. We respect the intellectual property of others. The information provided is believed to be reliable, but we cannot guarantee that the procedures and information given here will work correctly for your specific situation.

If you would like help with a computer or software problem you face, contact us. Send an email to request@stoneyhillassociates.com.

Want to subscribe to this newsletter? Just join our mailing list:

© 2006 Stoney Hill Associates, LLC