A word about cheap surge protectors

Typical $15 to $30 surge protectors use a device called an MOV (metal oxide varistor) to shunt surge current to ground. What you need to know about MOVs is that they wear out after a while. After a surge protector's been in service a year or so, it'll still work fine as an outlet strip, but it may not be doing anything to surges anymore; it may be just as if you'd plugged your PC straight into the wall. I sometimes put it that the main function of an MOV surge strip is to make sure your new PC doesn't get fried before it goes out of warranty.

The fact that MOV surge protectors wear out doesn't necessarily mean they can't get the job done. When you buy one, grab an indelible marker and write the purchase date on the side. When a year has gone by, chuck it and get a new one. Also, when you turn off your PC, make sure you turn off the switch on the surge strip too ... otherwise, you're burning service life on that MOV for nothing, so to speak.

I just plug my whole system into the surge strip with all the component switches on, and power the whole works up and down with the switch on the surge strip. That switch is usually at the cord end of the strip, which would tend to put it at the back, behind all the plugs. To fix that, I just zip-tie the cord to one side of the surge strip, so it will sit the other way, with the switch at the front.

There are more expensive devices that solve the problem in a more lasting way. UPS's (Uninterruptible Power Supply) generally isolate a PC completely from the house current. You also at one time could buy a power conditioner that used an active circuit instead of an MOV; that should cost more than an MOV surge strip, but less than a UPS.

High-end UPS's contain a large battery that's kept charged up from the line power, with enough capacity to keep the computer running for half an hour or so after the line power stops. They usually also have software and a serial port to connect to the PC, so that when the line power drops, the UPS can send a command to the PC to do an orderly shutdown before the battery power runs out.

See the Wikipedia and How Stuff Works articles on surge protectors for more on power conditioning.

I specified a big UPS with serial port for a consulting client once, and she had me test the automatic shutdown by pulling the plug of the UPS. It was a thing of beauty. First the UPS sounded an alarm; after a little bit when no response from humans was forthcoming, the PC politely closed all running software, shut down Windows, and turned itself off.

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