I have an old laptop that hasn't been opened or dusted for the better part of the six years I've had it, and when I took it apart to upgrade the storage, I found a lot of caked on dust on the motherboard and the inside of the housing. Some of it I was able to get rid of with canned air, but the motherboard is still pretty dusty, and almost looks muddy from all the caked on dust. I have a can of isopropyl alcohol that I've been told can be used to clean electronics, but I'm not 100% sure about whether it's okay to use that and cotton swabs directly on the motherboard to clean it.
Can you please advise if this is the correct method?
72 Answers
First, I suggest you not use compressed air to clean computers. Dust can be forced into fans.
Get a very soft small paint brush and a vacuum cleaner set to low suction. Brush the dust and allow the vacuum suction to pick it up. Hold the vacuum brush away from the board (not touching it) and use the paint brush to loosen dirt.
My own vacuum hose has a hole that I can open or close. Open that hole to reduce suction. Your own vacuum may have a different arrangement.
For dust, I would not use alcohol or any other liquid cleaner while the board remains installed in the computer, but rather keep it dry and brush out the dust.
This approach works for me in my own equipment.
Pure isopropanol is usually safe for this type of thing. Chances are though that unless you got it from an industrial or scientific supplier, what you have is not actually pure isopropanol (it's more likely either 90%, 70%, or 50% in water, as those are what you'll find most places that regular consumers would get it since most of what it's used for in the home is as a disinfectant and not a cleaner and pure isopropanol is actually not a very good disinfectant (it needs water to degrade proteins)). Additionally though, isopropanol may damage any plastics in the case, and using a liquid cleaner when you can't thoroughly douse the board (which you shouldn't do without removing it from the case) is not likely to be much help.
I would also recommend against using regular 'cotton swabs' as well, they may leave behind fibers if they get caught on anything, and those can either contribute to further dust buildup, or possibly cause thermal issues themselves. If you're going to use swabs, get decent foam ones that are designed for cleaning delicate equipment.
Compressed air is only really a decent option if you can guarantee no static buildup and the dust is only relatively light. If you're going to do this, make sure you're in an area with moderate (about 50%) relative humidity to combat static buildup, and hold the nozzle a bit away from what you're cleaning (and don't point it in a way that will blow dust into any fans, as you may end up blowing dust into the bearings and causing other issues. Also, if using compressed air, make sure to do it outside so that you actually get rid of the dust instead of just blowing it into the air inside where it will settle again somewhere else. Similar story with a vacuum, but you have to be even more careful there about static.
The approach I would take in your case is simple mechanical cleaning though. Get a small static-safe brush (you can get basic sets on Amazon for about 10 USD), and use it to carefully brush the areas with dust to loosen it up, and then either use compressed air or a small vacuum on a low setting to remove the loose dust.
