De-Dust Your Mac

Nearly all Mac models employ one or more internal cooling fans. Without them, your computer would overheat, leading to crashes, erratic behavior, and possibly even permanent damage to sensitive components.

But as the fans pull air into the computer, they also pull in dust. Dust can accumulate on the air intake vents, on the fan itself, or on any surface along the flow of air within the computer. When a layer of dust sits atop a hot component, it acts as an insulator, preventing some of the heat from escaping into the air. And if dust blocks the air flow, the heat that does escape has nowhere to go. Either way, your fan must work harder, which not only makes it noisier but also makes it suck in even more dust.

In short, dust is no friend of computers. By getting rid of the dust, you can make your Mac cooler and quieter—and prevent all sorts of unpleasant problems.

You can remove dust from the exterior case of your Mac with a soft cloth, but what we’re more concerned with here is the dust that gunks up ventilation holes and, to some extent, dust that has accumulated inside your Mac.

For the ventilation openings, you can use a soft brush, a vacuum cleaner with a hose attachment (but see the warning ahead about AC-powered vacuum cleaners), or compressed air. Of these, compressed air is usually the most effective at removing dust, but unfortunately it does so by putting the dust right back into the air. To deal with that problem, you can do your cleaning outside, or try holding the compressed air in one hand and a vacuum hose in the other, using the vacuum to suck up as much of the dislodged dust as you can.

Now, about the interior of your Mac…

If you have a Mac Pro (either the 2009 tower model or the 2013 cylinder model), you’re in luck! Both of these cases are trivially easy to open. Most other models pose more of a challenge. You typically need special tools, and there’s a real risk of breaking something, even if you have a pretty good idea what you’re doing. (And, any damage you cause while poking around inside your Mac won’t be covered by your warranty.)

I’ve disassembled and reassembled many Macs, including the iMac, Mac mini, and various MacBook Pro models. (And, without fail, I’ve found atrocious amounts of dust inside!) Taking apart computers is no big deal for me, but unless you have significant experience tinkering with electronics and a willingness to take risks, I can’t in good conscience recommend that you do anything that isn’t explicitly spelled out in your Mac’s manual (you can download manuals from Apple’s Manuals page) or the Mac support website.

Those warnings duly delivered, here are the general steps you should take to remove dust from the inside of your Mac:

1. Shut down your Mac.

2. If any part of the case is hot to the touch, wait for it to cool down.

3. Touch a metal portion of the case to discharge any static electricity.

4. Unplug your Mac; also unplug any peripherals or other cables.

5. Using your dust-removal tool of choice, remove dust from in or around any holes or slots on the outside of the case. Be aware that some of these openings may be on the bottom or the back of the case, depending on the design.

6. Following the instructions that came with your Mac (or available on Apple’s website) for installing RAM or other internal options, carefully open the case. The method for doing this varies from model to model. For example:

   • Mac Pro (2009) models have a side panel that you can remove without tools by pulling up a latch on the back.

   • Mac Pro (2013) models have a latch on the back near the top. Slide this to the right and then lift the cover straight up.

   • iMacs have only a small compartment for adding RAM (and the iMac Pro doesn’t even have that); further disassembly is tricky and probably best left to a professional.

   • Mac mini models from 2010 to 2012 have an easily removed panel on the bottom that provides access to RAM slots; see Mac mini: How to remove or install memory. Apple doesn’t recommend opening the cases of other Mac mini models.

   • MacBook Pro models from 2008 to 2012 require removing a bunch of screws on the bottom of the case; see MacBook Pro: How to remove or install memory.

   • MacBook Pro models from 2013 to present, and all MacBook Air models, should not be disassembled.

   • The MacBook (Retina, 2015 or later) shouldn’t be disassembled either, but then, it doesn’t have a fan, so it shouldn’t accumulate interior dust.

7. Again, remove any visible dust using your tool of choice.

8. Close the computer’s case, reattach peripherals and other cables, and turn it back on.

Clean Your Keyboard

Before you put away that vacuum cleaner or canned air, give your keyboard a once-over too, following these steps:

1. Unplug the keyboard from your computer (if it’s wired) or turn it off (if it’s wireless). For portables, turn off the computer.

2. Most keyboards cannot be disassembled easily, so don’t even try. Instead, simply invert and shake to dislodge any large particles. For larger or more stubborn particles, you may need to use tweezers or a slightly moistened cotton swab.

3. Run the vacuum cleaner or compressed air between all rows of keys.

4. Using a soft and very slightly damp cloth, carefully wipe the keycaps clean. (Some heavy-duty stains may require the use of a mild all-purpose cleaner, but be sparing, because liquid that drips into the keyboard circuitry can damage it.)

5. If you’re patient and your keyboard is especially cruddy, use a very slightly moistened cotton swab to clean the sides of the keys.

6. Plug your keyboard back in or turn it back on.

Make Archival Backups

By now, regular backups are part of your routine: your backup software automatically updates your archives every day and your duplicates once a week, and you diligently maintain backup media offsite—right? (If not, see Update Your Versioned Backup, a daily task, and the weekly tasks Update Your Bootable Duplicate and Rotate Physical Backups Offsite.) Even so, I suggest adding one final element to your backup regimen: creating archival backups.

If you’ve followed my advice, you already have versioned backups of all your important files—going back several months or more—on at least one hard drive (plus a second that’s stored offsite, or online backups). You also have one or more complete, bootable copies of your main hard disk as it existed at some recent time. This is all good, but some problems remain:

• Hard drives don’t last forever. Sooner or later—in a year, or in 5 or 10 years—you’ll no longer be able to access the data on your drives.

• Because backups constantly get bigger as you add files, they can eventually outgrow the drive you store it on. (Time Machine and some other backup apps partially address this problem by automatically purging older backups when your drive gets full, but they may not offer an easy way to keep copies of those old files if you still need them.)

• As your main disk fills up, you may want to delete files periodically to save space (see Remove Unneeded Files, next) and yet be able to retrieve those old files if you later need them.

I’m aware of several schools of thought regarding archival backups, so bear in mind that this is just one person’s take on the process. In a nutshell, I recommend this: every few years, set aside a full backup on separate physical media, store it in a safe place, and then either start over with a new backup drive or recycle your existing backup drive by erasing it and backing up from scratch again. By doing this, you hedge your bets against hard drive failure, free up valuable space for new backups, and give yourself a safety net in case you want to prune files on your primary hard disk.

In previous versions of this book, I suggested using a stack of recordable DVDs as your archival medium. Nowadays, I think that’s a suboptimal choice, because:

• Macs with built-in optical drives are nearly extinct. Even if the Mac you have today can record backups onto DVDs, the Mac you have next year might not be able to read them.

• DVDs don’t last forever. Although some brands are better than others, your data could begin to deteriorate after only a few years, even if you store the discs carefully in a dark, cool, dry place. As I say in Take Control of Backing Up Your Mac and Take Control of Your Digital Legacy, “archival-quality” media exists, with claims that it will preserve data for a century or more. (For example, the makers of MDISC media claim it will last for 1,000 years.) But no one knows for sure, because it hasn’t been around that long yet.

• Backups to, and restores from, optical discs are slow and inconvenient—and many Mac backup apps don’t handle DVD backups gracefully.

So, I’m not going to say unequivocally not to use DVDs, but I think you’d be much better off with another option:

• An extra hard drive: External 4 TB drives usually cost less than $100, and lower-capacity drives are even cheaper.

• Archival cloud storage: Several online services offer dirt-cheap online storage that’s ideal for long-term backups, sometimes with the qualification that accessing your data later isn’t quite as speedy as conventional cloud storage. Examples include Amazon Glacier, whose pricing varies by region but starts at $0.004 per gigabyte per month, Google’s Cloud Storage Coldline, which costs $0.007 per gigabyte per month, and Wasabi, which has plans starting at just $0.0039 per gigabyte per month. To back up to one of these services, you’ll need special software; my recommendation is Arq.

If you choose an extra hard drive, the simplest procedure is to put your existing backup drive(s) in storage, set up your new drive exactly as you did originally, and create entirely new versioned backups and bootable duplicates that you’ll update on that drive for the next few years.

If you choose cloud storage, copying an entire drive’s worth of data (both versioned backups and a bootable duplicate) to the cloud doesn’t make much sense; it would take forever and restoration would be complicated. Instead, I suggest making a full versioned backup to the cloud location and updating it occasionally—say, once a month for six months or so. Then erase the local disk or partition you use for versioned backups and start over with fresh backups.

Remove Unneeded Files

Just as your home probably needs a good spring cleaning once a year, your computer can use a digital tidying-up now and then. So take this opportunity to get rid of apps you don’t use, outdated files you’ll never look at again, and any other crud that has gathered in the dark corners of your hard disk.

The process is the same one I described near the beginning of this book. Flip back to Clean Out Accumulated Cruft for complete instructions, and repeat that procedure now.

Check Your UPS Battery

In Use a Surge Protector or UPS, I urged you to be sure your computer itself, and any other equipment attached to it with cables, is connected to a surge protector—or, better yet, an uninterruptible power supply (UPS), which not only provides backup electricity in case of a power outage and protects you from voltage spikes but also conditions the power coming from your AC outlets to smooth over any irregularities that could damage your computer.

UPSes are powered by rechargeable batteries (usually big and heavy ones) and, like all batteries, these eventually wear out. Depending on the type of battery in your UPS, the design of the device, and assorted other factors, this battery can be expected to last between three and five years, give or take.

When your battery reaches the end of its useful life, it must be replaced. In some cases, that may require you to return the entire UPS to its manufacturer, whereas in other cases you can simply buy a new battery and pop it in yourself. Some lower-end UPS models have batteries that can’t be removed, so you must replace the entire device when its battery expires. Regardless, most UPS manufacturers offer programs for recycling old batteries in a convenient and environmentally friendly manner.

But here’s the thing: you shouldn’t wait until your UPS starts beeping, blinking, or otherwise complaining that its battery is at death’s door before you do something about it. Replacing batteries, or UPS units as a whole, can be somewhat time-consuming, but if you don’t take action in time, you could be left without protection when you need it most. Therefore, I recommend preemptively changing your battery before you think you need to.

Specifically, you should first refresh your memory as to when the UPS (or its current battery) was purchased—for example, by looking it up in your bank statement. Make a note of this date in a place where it will be easy to find next year, such as on a piece of tape on the UPS itself. Then, given a UPS whose battery is rated to last five years, do the following once a year:

• If the date of purchase is less than three years in the past, you’re done. Your UPS battery should last at least another year.

• If the date is between three and four years in the past, check the manufacturer’s site to learn about their battery replacement and recycling policies and to find out whether a new battery is in stock, how much it costs, and so on. Keep this information handy, on the off chance that the battery has an unusually short life span and you have to replace it early.

• If the date is more than four years in the past, immediately start the procedure for replacing the battery (or the entire UPS, as the case may be).

If you do this, the odds are good that your battery will be replaced soon enough, but not so soon that you don’t get your money’s worth.