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Name: William H.
Status: Educator
Age: 30s
Location: N/A
Country: N/A
Date: 2002

Constantly booting and closing my system down will in time be no good for many of my components as you know. Will I be better simply leaving my system running constantly. If not would you please explain why. I have a friend who rarely switches his systems off. I have four systems networked at home.


There are two schools of thought with regards to this. First are the frugal people. They feel that by leaving the system off, they are saving electricity, and in turn saving money. They also think that turning it off will minimize the chance of it getting hit with a surge. Not so,since I have seen surges pass through phone wires while the computer was off (lightning strike). The second group of people are the 'propeller heads' as dubbed by friends of mine. We know that the system board on a computer is full of solder points. Given that, when a solder point is heated up and cooled down over and over again (such as turning on and off the computer) the solder becomes brittle and has more of a chance of breaking. Therefore, we leave the computer powered on all the time. Do not get me wrong, all computers need to be rebooted on a regular basis so as to avoid problems. I have a one month maintenance reboot on all of my servers at work. It all breaks down to what type of person you are. ;-)

I hope this helps!
Nick Hitchcock

You are correct, I am in the same situation. I not only leave my work computers on but my personal system as well. One advantage is when the system is running it is at a constant temperature. If you shut your computer off, it is no longer generating heat, thus allowing components to cool and contract. When you turn your computer on it then generates heat and causes the metal components to expand. All of this expanding and contracting over time can cause pieces to fail, such as components that are soldered to the motherboard thus ending up with a system that has reached its end of life quicker than expected.

Best Regards
Joe Noga

There really are not any hard rules here. Each time you turn your system on and off, it places a great deal of stress on the parts. Just like a light bulb rarely burns out except when you turn it on, if a component is going to destroy itself, it will often do it when you turn the computer on.

Leaving your system on will tend to save the expensive components like your processor, memory, video card and things.

But, moving components, like the fans, will tend to wear out the more they are left on. Additionally, you will use more power and run up your electricity bill by leaving your computer on. I have worked with computers for several years. I have had power and CPU fans fail more often than any other parts. They seem to always fail on the systems I leave running constantly. On systems that I turn off when I am done using them, I generally have not had much trouble with parts failing, even though they are under increased stress.

In some cases there are other considerations. If you have a cable modem or DSL connection, you may be vulnerable to hacker attacks whenever your system is on. If you use a single server to connect to the Internet, then you may need to leave that system on so everyone can use the Internet.

So, I generally follow a simple compromise. My server is always on, but has firewall software installed to help reduce the risk from hackers. My other machines are turned off whenever they are not going to be used for a while.

I hope this helps. As I said, everyone has to make their own judgements about what is best in this case.

Eric Tolman
Computer Scientist

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