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Practical Computer Advice
from Martin Kadansky
Volume 3 Issue 10 October 2009
In This Issue
Should I leave my computer on, or turn it off?
Which is better, leaving your computer on all the time, or turning it off? Here is my advice on how to take good care of your computer hardware.

Should I leave my computer on, or turn it off?

When I get this question, usually the question behind it is "What can I do to make my computer last as long as possible?" While all computers wear out eventually, there are several things you can do to make your computer last longer, but some things will still be up to chance.

Things you can control:
  • Leaving it on vs. turning it off
  • Removing dust and pet hair
  • Surge protection
  • Backup
Things you can't control:
  • How long before your computer's components wear out
Leaving it on vs. turning it off
When it comes to computer hardware, there are two schools of thought regarding wear and tear:
  • What wears out electronics over time is accumulated heat. Thus, you should turn your computer off (or put it to sleep) so it has a chance to cool off.
  • What wears out electronics are the little surges that are a normal part of powering up a computer. Thus, you should minimize how often you turn your computer off.
There is some truth to each perspective, but you obviously can't do both.

Here's the clearest advice I've gotten on this issue: The wear and tear to start up a computer is roughly equivalent to about 4 hours of regular use. This means that:
  • If your computer is on and you're taking a break, but you'll be back to use it in less than 4 hours, just leave it on.
  • If it will be more than 4 hours before you'll be back to use the computer again, turn it off or put it to sleep. For example, you may decide to shut your computer down at night (or put it to sleep) and turn it on in the morning.
However, there are a few exceptions:
  • If your computer is acting as a "server," i.e., someone else's computer may need access to it at times that you can't predict, then you should leave it on. For example, if your computer shares its files or printer with other computers on your network or over the internet, turning it off (or permitting it to sleep) will make those resources inaccessible.
  • If your computer has been on (or sleeping) for more than a week or two, it may start acting strangely or running slowly. Shutting it down (not sleeping, standby, or hibernating) and turning it back on again often clears this up.
Removing dust and pet hair
Most desktop computers have an exhaust fan that pulls cool air in through vents on one side of the case and blows warm air out the other. This usually works well, but over time, layers of dust, and pet hair (as well as cigarette smoke, carpet fibers, etc.) can accumulate on the inside of the computer, forming a "blanket" over the motherboard that keeps in the heat. The exhaust fan itself can also get coated, making it less effective at cooling. The result is increased heat inside the computer, which can cause it to act slowly or strangely, shortens its lifespan, and can eventually cause it to fail.

Some laptops have exhaust fans and some don't, but they still accumulate dust inside, especially through the keyboard, which is usually located right over the motherboard.

How can you tell if this is happening to your computer? Look for wisps of dust around the computer's case, especially on the cooling vents and exhaust fan, and under the keys of your laptop's keyboard.

How can you clean the dust out of your computer? While it's certainly possible to take your computer apart and clean it (some recommend vacuuming, others recommend blowing the dust out with compressed air), since there are so many ways you might damage your computer's fragile little electronic parts, I recommend having a professional computer person do this for you, ideally every year or so.

Surge protection: Yours is probably already worn out
While you can't prevent surges from coming over your electrical lines, you can improve your surge protection. You've probably owned many computers over the years, but if you're like most people you're still using the same surge protector you bought 5 or 10 years ago. My hardware repair colleagues tell me that surge protectors quietly wear out over time as they protect your equipment from little surges that occur fairly frequently. In other words, an old surge protector is probably no better than no surge protector.

I recommend that if your surge protector is more than 4 years old, go out today buy a new one to replace it. If you can't remember how old it is, it's time to buy a new one. I'm not convinced that a $50 model is any better than a $10 one, as long as you get a surge protector, not just a "power strip."

I also recommend that you before you plug in your new surge protector, take a marker and write directly on it "Replace me in <month><year>," picking a date 4 years from now. That way, you'll see its "expiration date" and you'll be more likely to replace it next time in a more timely fashion.

And, while you're buying a new surge protector for your computer, buy another one for your television, stereo system, answering machine, cordless phones, and any other important or expensive electronic devices you may have, and mark it "Replace me in ..." as well.

Backup: Cheap insurance against hardware failure
Since your computer may fail or wear out without any warning, even if you take very good care of it, backing up your important data is more important than ever. The cost of a good backup system (easily under $200) is far less than the cost of a data recovery service ($1,000 or more), not to mention the potentially devastating cost to you if your data is permanently lost. Backup is cheap insurance against hardware failure, especially if you can't replace your data or you're running a business. Don't learn this lesson from a disaster!

How long before your computer's components wear out: 3 years?
Computers prices are lower today than they have ever been, but (in part due to cheaper components) they also have shorter lifespans than previous generations. My repair colleagues tell me that many hard drive manufacturers only give a 3-year warranty on the hard drives inside most computers, so from that perspective if your computer is more than about 3 years old you're "living on borrowed time."

Where to go from here
  • Review your computer habits and adjust when you leave it on vs. turn it off or put it to sleep.
  • Check your computer for dust, have it cleaned regularly.
  • Buy a new surge protector, mark it with an "expiration date."
  • Set up a good backup system. See "What's the single best way to protect my computer?" http://www.kadansky.com/files/newsletters/2007_12_19.html
If you know someone who might find this helpful, please feel free to forward it.
If you have any comments about this article, send me a reply!
If you have a topic that you'd like me to write about, I'd love to hear about it!
How to contact me:
email: martin@kadansky.com
phone: (617) 484-6657
web: http://www.kadansky.com

On a regular basis I write about real issues faced by typical computer users. To subscribe to this newsletter, please send an email to martin@kadansky.com and I'll add you to the list, or visit http://www.kadansky.com/newsletter

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Copyright (C) 2009 Kadansky Consulting, Inc. All rights reserved.

I love helping people learn how to use their computers better! Like a "computer driving instructor," I work 1-on-1 with small business owners and individuals to help them find a more productive and successful relationship with their computers and other high-tech gadgets.

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