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How do you safely clean the inside of your desktop computer?

May 22, 2014 11:04PM PDT

How do you safely clean the inside of your desktop computer?

I hope some of you techies can help me out. I was doing some cleaning around the house, and while I was cleaning out my office, I noticed that my computer box vents were grossly blocked by a blanket of dust. Even the back of my computer where all the cords are connected to it was covered with dust and spider webs. OK, I'll admit I'm not a clean freak, and to be perfectly honest, I have never visually checked my physical computer up close since I had purchased it. I did some wiping on the exterior of my computer, but that only got me so far, as I could still see a lot dust on the fans in the inside. I did manage to buy one those canned air, but spraying it from the outside cleared the vents, but now all the dust is inside. I desperately want to open the computer up, but I'm not sure how to. Here's the caveat. Opening it is one thing, however my biggest fear is I'm afraid I might break something or touch something inside I'm not suppose and render my computer useless. I'm sure dust isn't good for the computer's health and I'd like to give the computer a good cleaning. Can you help me with this? I'm not particularly mechanically inclined, but with a good set of instructions on how to clean the inside of a computer, what not to do, and how often computers should be cleaned, I think I'll be OK. Please help and don't laugh as I'm a complete new comer to this. Thanks for listening, and I appreciate your help in advance.

--Submitted by Miranda S. L.

Discussion is locked

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May 22, 2014 11:23PM PDT

Open it up and vacuum it out. Spraying canned air just spreads it everywhere and places you don't want, as you discovered already. Some places may need wipe with a damp (distilled water only! no cleaning solution like windex) linen cloth, (not washrag, not cotton ball, not Q-tip, etc.) but try dry cloth with vacuum close to it first. Damp is not dripping. If you did need to use a damp cloth, vacuum air past the areas till it's dry for sure before using computer again.

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Take it outside to clean it
May 23, 2014 4:36AM PDT

That way you don't mess up the house. Use the blower end of a shop vac or canned air. There are some concerns about static electricity created by vacuum cleaners so many folks don't recommend getting too close with the vacuum hose or wand. The blower end usually works better than the vacuum end. Also, using a paint brush on fan blades and heat sinks loosen the dust. Your PC is more likely to collect dust the lower it sits toward the floor. Force air through both fans and the PS both ways until you can no longer see a cloud of dust created. Hold the fan blades still while blasting them with air as well. This will take all of 5 minutes once you get it opened up and outside.

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not shop blower
May 23, 2014 10:16AM PDT

no matter how much you clean them, something can always blow out into the computer. Canned air would be better. The problem I have using any sort of blower is it can more easily put stuff under slots on the motherboard, where it might also encourage corrosion due to humidity. Recent thread in fact on corroded motherboard and humidity. Although a vacuum can do the same, it's less likely.

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Unless you use a brush attachment
May 25, 2014 6:55PM PDT

on your vacuum, you won't loosen that dust. It's a brush attachment to a hose type vacuum that I was told not to use due to possible static discharge from touching components. Everyone is going to have their own feeling about static. In my work, we might have been oversensitive about it...needing static mats, static free gowns, etc. We did use canned air but it has the downside, as you said, of just forcing the dust to an exterior space where it can be brought back in. For my own purposes, I will clean my PC about twice a year with the blower end of a shop vac and a 1" paint brush for removal of stuff that gets stuck. That works but doesn't get it all. One can be a bit too fastidious, I think, and risk doing more harm by digging and scratching for the last speck. When the time comes for component removal and thermal paste, I'll do more. I'll even take out the PS and open the case. I'll pull out the video card and clean the heat sinks better (no fan in mine). I may reseat cables at that time as well. It just seems better to do minimally invasive surgery on a regular basis rather than make deeper cuts when problems start.

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No brush attachment!
May 26, 2014 2:44AM PDT

That is a bad idea, as you say. However, a vacuum alone will remove the major portion of the dust, if you help stubborn portions along with your fingers (after grounding to the case). I have used a small paint brush, but very carefully, since any brush can cause a static charge. Any rubbing will create a charge, and brushes of any kind have a lot of surface to rub. It is best to touch the electronic components only as needed. Of course, if you are grounded to the computer case with an anti-static strap, you have eliminated most of the problems associated with static.

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May 30, 2014 11:35AM PDT

I've had good luck spraying a brush or vac attachment very lightly with anti-static spray. Most of those kinds of spray are volatile enough that they dry almost instantaneously, and don't leave any chemicals behind. I never use it on the parts, only the brushes. I only do this in surface areas that don't have electronic components in the surface. I don't do it to motherboards or cards with chips in it, etc.

What would be ideal is having a cardboard box booth with a vacuum cleaner running at the only open end and the system unit inside, where you can blow off the circuit boards with canned air, and the resulting clouds of filth can be carried away by the low air pressure environment. It would roughly be like those auto-shop bead cleaners with the glove ports to hold the canned air. Any kindergarten craft-work lover could build it in a flash, then throw the whole thing away when finished. I've built quicky paint booths in similar ways. Duck tape does wonders! HA! Happy

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Static discharge
May 31, 2014 1:06AM PDT

Working in the PC support industry, before cleaning the inside of your computer with canned air, vacuums, brushes etc. I would recommend taking necessary precautions to properly ground the system unit. The amount of ESD (electro-static discharge) that can damage your system board is far less than the static shock you get touching a door knob after walking across a carpet. It's at such a low charge that you would not even feel it.
For those allergy sufferers you may also want to wear a dust mask if working indoors where the displaced dust\debris can't be contained.

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Jul 10, 2014 3:00AM PDT

I have been told by many not to use a vacuum cleaner inside the CPU box. Now using the blower end may work as well as compressed air in a can. If using the air in a can, I use some from three or four cans. As you spray the can gets very cold so to limit that, I use a little out of each can. Be sure if any components are sprayed to closely and show signs of white moisture, to ensure to leave that area alone until it completely drys.

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NEVER use a vacuum cleaner
Sep 12, 2016 5:07PM PDT

Never, ever use a vacuum cleaner to clean out your PC. You run the risk of creating a static charge that may fry sensitive circuitry. A sable or bristle paint brush, isopropyl alcohol, a can of compressed air, microfiber cloth, and thermal paste (if you're going to clean your PC, may as well go the full 9, right?) is all you'll need; probably costs around $40-50, much better than finding out you need to replace your GTX 1080 because you fried it. Clean it outside or somewhere static free and away from where your PC usually sits, and take your time.

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it's good option
Sep 13, 2016 3:14AM PDT

cleaning with vacuum is good option. But i only clean my pc with a brush which help to remove dust. Is it necessary to clean pc???

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I Use Compressed Air
May 23, 2014 5:00AM PDT

It's fairly easy and I've used such on hundreds of computers at the job. In my opinion, it does a better job than a vacuum and it also allows you to avoid any static electricity that occasionally occurs with a vacuum.

Disconnect the computer from all cords and cables. Take it into the garage and set it on a table or workbench. Remove the side panel from the computer tower case. Most of those panels can be removed easily by using a Phillips-head screwdriver to remove two screws on the back side of the tower. You should now be able to see everything on the inside of the computer. Then use the canned air to blow out all the dust from the power supply, the processor and heatsink area, all fans and vents and everything else inside. Be careful to NOT cause the fans to spin excessively, (I usually hold a Q-tip or pencil on the fan so it doesn't spin), as high speed spinning of the fan could cause damage.. When you're finished, replace the side panel, put the computer back into its space, and plug all the cables back in.

In my home garage, I have a small air compressor that works fine for me.. I am able to adjust and turn down the pressure and use it.. ONE NOTE: Many older air compressors will have small amounts of condensation inside, which causes water to be sprayed through the line. If that's the case with yours, DON'T use it, as water is not a good thing for computer innards.

Hope this helps.


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One downside of canned air
May 23, 2014 6:38AM PDT

is that the inside of the container cools very rapidly and the pressure drops. As well, you need to keep the can upright or it will spray the liquid propellant on your workpiece. This is generally harmless but I'm not sure about today's lead free solder and if this rapid cooling of the metal and substrate might not fracture something.

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(NT) Yep, Keep Those Small Cans Upright !
May 23, 2014 8:44AM PDT
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Regarding air compressors
May 27, 2014 2:26PM PDT

I agree with your recommendation. I would like to add that it is important to use a compressor with an oil-free pump. Usually these are the small light-duty compressors. Oil lubricated compressors usually used for driving tools may spray tiny droplets of oil, which would certainly not help the dust problem long term.

Most of the time I think moisture is not too much of a problem especially if the compressor is not run for too long a time period. The main thing is to let things dry if any condensation occurs. Pure (condensed) water is not really all that harmful to electronics as long as they're not energized, aside from the possibility of corrosion (but that would probably require a fair amount of water). You are right about being cautious of course. My point for the original poster is just not to be excessively worried about it.

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(NT) An air dryer filter helps on the compressor as well
May 30, 2014 11:37AM PDT
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I use compressed air.
May 30, 2014 2:18PM PDT

I also have used compressed air with the canisters you can buy from any electronics store. I also have used my small 2 gallon shop compressor. It works Very, very well on the 30 lb setting and yes there may be some moistyure in the tank. To combat the tank moisture I tilt the tank so that the drain valve is pointing straight downwards and open the valve enough to lest the water accumulation in the to drain. You should be safe to blow out your desk top components.

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I Use Compressed Air
May 31, 2014 3:24PM PDT

You saved me the trouble of posting my own opinion; my shop compressor and a pencil is all I ever need. I have a water separator on my compressor for good measure.

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Hi Grif
Jun 2, 2014 10:22AM PDT

I don't mean to go off topic here but had read your post in the newsletters I still get from CNET and wanted to say hi to you. You've been a BIG help to these forums for many many years. I don't know if you remember me but I was a mod for the Computer Help Forum with Toni Hackler about 13 yrs ago. Thanks for all your help over the years & your patience to me and so many others. Grin

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Of Course I Remember.. Good To Hear From You !
Jun 2, 2014 10:52AM PDT

You gave your share of good advice here as well..

Take care.


Post was last edited on August 17, 2016 9:02 AM PDT

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I remember you too
Jun 7, 2014 6:21AM PDT

glad you're still kicking. I was a mod there with the both of you then.

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hi Jim
Jul 14, 2014 6:26AM PDT

I do remember you. Hard to believe so many years have come & gone already. Hope all is well with you. Happy

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yes, older
Jul 14, 2014 1:23PM PDT

two children already out of the house, a 15 yr old left, grayer hair, weaker knees, and really tired of the cold winters here in Maryland.

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Jul 14, 2014 4:09AM PDT

Very sound advice. But...

I am handicapped and find it difficult to transport the CPU case to another room. I was concerned that the air spray was blowing the dirt elsewhere, rather than removing it. I always use a grounding strap when working inside my computer, and rub the frame every ~ minute.
I was informed that effective vacuums for cleaning electronics are professional and cost hundreds of dollars (surely they must have some sort of antistatic device installed).

However, after reading your post I realize that a thorough cleaning with air spray is the safest and most effective way to go. I was also told that some electrical "cleaner" sprays will leave a residue, so I ruled those out at the beginning.

I will therefore 'bite the bullet' and transport my cpu case elsewhere; the garage is too far for me, but this is a big house and I can find an empty and CLEAN space to do the cleaning. I do not want to be blowing exterior dirt inside; that would certainly defeat the purpose.

Again I thank you muchly for your input and confirmation of the proper procedure for cleaning my computer.

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With some care....
May 23, 2014 8:43AM PDT

...but you don't need to be paranoid about it, Miranda.
All the replies so far are perfectly reasonable as answers to the question, but a lot depends on your level of confidence, expertise and what tools you have available.

For a quick cleanup all you really need is an artist's backwash brush - about half an inch wide is ideal - and a small vacuum cleaner; with the side casing off and the tower lying on its side, just use the vac nozzle to remove all the heavy deposits from the case floor, the PSU vents and around the fans.
You don't have to touch anything with the nozzle - just in the general area will normally suffice for the loose stuff; however if you have really thick, clingy stuff you can use the brush to dislodge it and the vac will take it away.

Some folks have mentioned using compressed air - and to be fair, it does work well enough but you DO run the risk of driving stuff into places where it shouldn't be; if it's that bad, then the only safe way of doing the job is by doing it properly, i.e. take the whole thing apart, clean off all the components and re-assemble it.

Likewise some have advised disconnecting all wires to the tower, but the problem with that is if you disconnect your power lead, you also disconnect the ground wire that allows any ESD to escape via your mains cable.
Keep the plug connected, but with the positive side isolated, either at the wall socket or the switch on the PSU.
Lastly, leave the side panel off the case until you've booted the PC and made sure that everything is as it should be - there's nothing worse than boxing everything up, only to find you've forgotten something!

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With MUCH care!
May 23, 2014 10:32AM PDT

NEVER leave the power cord plugged in when you have the case opened! Especially in newer computers! The highly touted fast startup by Windows 8 systems comes from the fact that the computer goes into a modified sleep state rather than fully powering down. This not only allows many processes to keep running but obviously it means the entire system is fully powered. If you want to curl your hair and your computer, leave it plugged in. On the back side of most computers there is a real power switch. The On/Off switch on the front doesn't power down most computers!

Get a static bracelet from an electronics supplier if you plan on touching the internals of your computer. That's a bracelet that has a wire that can be fastened to a grounded metal object or inserted into the grounding port of an electrical receptacle. Just for cleaning you don't need a grounding bracelet unless you're very shaky.

There are special anti-static vacuums you can buy for cleaning electronics. These have well grounded hoses. Regular vacuum cleaner hoses are not wire cored any more and of those that are, the wire is not grounded to the vacuum case. A sharp spark of static and your electronics are toast. Don't use your household vacuum, even to blow if you can use the exhaust port.

Canned air is best. If you have an air compressor, as was mentioned elsewhere, you can force some moisture into your computer unless the air first passes through a desiccant - dryer cartridge, or you allow the computer to air dry under an air current (fan) for at least an hour before you put the case back on and hook up the power. Using canned air is like spray painting, keep the nozzle or the tube at least 8" away from any object. If there's a propellant used, it cools when it expands and can thermal shock your electronics. Pure compressed air has no propellants to worry about, but still, to be safe from damaging the surfaces, keep the nozzle or tube at least 8" away. Use a suitable paint brush, artists type to loosen stubborn dirt and Also mentioned was blocking the fans from spinning. YES! Spinning the fans too fast can ruin the bushings and cause the little fans to seize and stop running. Use a small wooden dowel rod to reach into the fan blades to hold them still.

I noticed that you said you don't know how to open the case. Puzzles they iz! On some you can remove a few screws on the back and the case will easily slide back or up. On others you remove the screws and lift the case about 1/8" and then slide it back. On others you slide it back 1/8" and then lift. On others there are actual latches you have to find and release. A few you have to spread one edge of the case to disengage some tabs. Do a web search on your brand and model with the term 'To remove the case from __' or see if you can find a full service manual to download from the manufacturers' site.

Next, how often to clean? I've got two dogs and four cats in a house with forced air heat. About every three to five months is plenty for me. For other homes, you might go 2 months or even a year or more between cleanings. The answer for you? Take a look at the vents and just inside through the vents with a flashlight every few months and you'll get your answer.

Finally, if you feel the least bit uncomfortable doing this, find a family member or a friend who isn't, or take your computer to a good, well recommended shop for them to do it. For some people this is nothing, for others, it can be a top level challenge.

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Begging yer pardon but...
May 30, 2014 9:33AM PDT

...I DID say 'with the mains switch isolated' - and unless Redmond has found a zero-rated OS that doesn't need any power, I'd still advise that the PC remains plugged in while cleaning is taking place.
Heat and ESD are the biggest killer of electronic components - and a casing earth wire is the easiest and safest method of preventing ESD damage.

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cleaning inside computer
Jun 1, 2014 11:01PM PDT

I can still clean by unplugging everything on the computer to avoid static electricity. Sometimes using just a small feather duster Very Lightly has helped me. But I try to avoid touching anything inside with it!

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Correct earthing is easy, static is all over.
Jun 2, 2014 5:04AM PDT


At your computer shop get an earth link made up. Apiece of wire about 1.8 metres. six foot with two crocodile clips on each end. It must also have a wristband for yourself. UNPLUG the PC from the mains. Go to a room with NO carpets or a concrete floor. Work on hard surfaces without material covers. Open the PC as described above. Clip the earth link to your PC, yourself and a steel window frame or a cold water tap. Use a small brush as Grif says and wipe out most of the dust. Just hook it and do not using wide sweeping motions as this causes static build up. Now remove the thin layer of dust with an air can.

You can also use Iso Propyl Alcohol to clean your motherboard. This kills static dead and removes the dust well. DO NOT use Lacquer Thinners! Done? Re-assemble and replug and enjoy!

Congratulations on your courage to ask the question.

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cleaning with earth link
Jun 2, 2014 9:00AM PDT

This sounds complicated. I have had success with just pushing the power button while everything is unplugged to ground the computer. Then opening it up where I can whip up the dust with a damp towel or the duster. Mainly I rub around the periphery of the inner casing and around the fan blade without touching any circuits.

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Grounding the computer ?
Jun 4, 2014 8:23PM PDT

It's the correct proceedure to unplug computer first. Followed by depressing the power button, which quickly bleeds the capacitors and components capable of holding a charge. After power down, the computer should be opened up on one side or both. We here at Lockheed Mil standards and calibration lab use compressor air to blow the dust from the entire insides. Sheilds are removed, like those in IBM desktops and some older Gateway computers that port air directly onto the heat sink for the CPU. That usually gives access to dust removal choked within the cooling fins. I have never burned out a case or power supply fan using compressor blown air on them but certainly holding them from spinning is a good idea. Wipe down the interior side panels of dust before re-installing on unit sides. As a part of PM, we will reseat any chips that sit in sockets, like PROMS and ROMS by pressing down firmly on the chip. Sometimes, also as PM, we will remove the memory chips and clean the gold contacts with a pink pearl eraser then reseat them in the memory socket.