I recently had to take my iMac apart in order to look at the hardware closely, and after 5 years of intense use in my home office, I got a chance to re-convince myself of the importance of keeping one’s computer tidy inside, not just outside.

Apple doesn’t make it easy for us to service our computers, do they? Gone are the days of the big Power PC or Mac Pro enclosures that could be easily opened for a bit of vacuuming and dusting or the upgrade/replacement of a piece of hardware. Or how about those unique and colorful 1st gen iMac enclosures that were transparent, so you could see at a glance if they needed a bit of inside cleaning? The enclosure of my iMac G5, though impressively thin for its time, with components tightly packed inside, was still fairly easy to open. Even the predecessor of my current iMac, a 2011 model, was easy enough to open, because the display was affixed to the enclosure with magnets. These days, the enclosures of our Macs are sealed with adhesives that make it difficult to get inside…

The IT part of me gets it somewhat: if they’re too easy to open, most people will only get inside and mess something up. Plus, an accidental spill of liquid on the screen, or an overly judicious application of cleaning solution, might get inside and affect the circuits.

It’s easy and natural to assume that if a computer is sealed shut, it’s clean inside, but the truth of the matter is that computers need to be cleaned and serviced regularly. As long as a computer has active cooling (a fan that pulls air in), dust will get inside and settle everywhere. Even passive cooling involves some sort of air current that moves through the machine and dust will follow that current and accumulate inside over time.

Here’s what the inside of my iMac looked like when I opened it up for the first time.

It may not look too dirty at first glance, but let’s have a closer look, shall we?

I took every single piece apart, and every piece was full of thick dust like this, dust that would have clogged up the air vents completely and caused an overheat or even a shortcircuit. It was very fine dust that kept getting into my nose and making me sneeze. I couldn’t believe how much of it had gathered inside. This iMac’s always been on my desk, in my office, a room which I vacuumed regularly, but as you can see, five years of moderate to intensive use for 8 or more hours per day, will definitely show up on the inside, even though the outside is shiny and clean. This is why I believe every Mac owner ought to either learn how to clean their computer or take it into a repair shop every few years to have it properly and thoroughly cleaned. We have plenty of resources these days. I used the thorough guide for taking apart my iMac posted on iFixit.com, a resource I definitely recommend.

If and when you take your iMac apart, you should definitely check the air intake vents (located on the bottom bezel of the enclosure) and the air output vents (located behind the flex mount of the iMac’s foot, above the RAM bay). That’s where dust will accumulate the most.

Here’s how my computer looked after being properly cleaned.

Please be careful as you handle the various parts, will you? One wrong move with the screwdriver and you could damage a circuit or worse, if you’re handling the power supply, you could cause a short that could give you a real shock and damage it for good. Unless you work in IT and have handled computer innards before, your best bet is to find a reputable repair shop, hopefully an Apple-authorized one, and have them clean it thoroughly. Just so you don’t have any issues with your Apple warranty and perhaps void it by mistake, do this operation after the warranty runs out (that’s 3 years for Apple Care).

Hope this helps!