Ride the Lightning
Twice in the past week I’ve replaced hard drives due to power issues. Of all the components to replace on a computer, the hard drive is the most time consuming and risky to your data. First, out of responsibility to my industry, back up your data! If you are unsure how to do this, use a reliable managed IT service. There, I’ve said it, we can move along now. What I want to discuss today are some inexpensive things you can do to prevent trouble. Both of the incidents I just worked on were completely preventable, had a few precautions been taken. Let’s take a look at these and find out what could have happened instead.
Case 1: Electronis Incompetous
The workstation next to his was acting up, so, the helpful user unplugged the workstation. It still didn’t turn off, he heard the fan stop, but the computer was still on. so he plugged it back in, waited 15 seconds, and did it again. Still it stayed on. He did this 3 more times. Finally he noticed that it was his station, not the malfunctioning one he was unplugging. By this time the boot sector of his hard drive was like a 6 year old boys plate of asparagus, all mushed around so it looks like nothing’s really there.
Ok, in 29 years of computer repair this was the first time I saw this. But I have seen many a hard drive crash by having the power turned off and on repeatedly. Here’s what’s happening – the drive plates themselves, called platens, are spinning at up to 10,000 rpm. The heads are small metal blocks that are suspended above and below the platens with less than the thickness of a human hair in between. There are magnetic as well as centrifugal forces at work with each other. When the power is cycled off and on the forces start to work against each other. This significantly increases the chances that the heads will collide with the platen causing what’s called a “head crash”. This nearly always damages data, and often requires the drive to be replaced.
If your computer is locked and won’t shut down, here’s the first tip. Try holding the power button down for 7 seconds. That will usually force a shut down. It’s not friendly, but better than pulling the plug. Second, when you power it on, let it stay on for at least 2 minutes before shutting it down again forcibly. That should give the drive time to spin up to speed, and usually get the heads out of the boot sector (the most vulnerable area). Third, if it locks a second time, it’s time to call in the cavalry. There are rarely problems of that nature that will heal themselves. You need some expert advice.
Case 2: Power Double-fail
The power failed at a customer’s site. Occasionally it happens. When the power came back on, one of the computers wouldn’t boot. And never did again. Now it is possible that this was an example of the previous case. But when there is an outage, new factors can come in to play. Electronic devices have what’s called inrush current. This is the extra energy it takes to spin up motors, heat stuff up, light up bulbs, etc. The power company has plenty of energy to keep everything rolling, but with inrush current taking up to double the normal operating amount of power for a device, imagine what happens when every device in the neighborhood does it all at once. It creates a sag on the voltage throughout the system. That’s what happens when the power comes back on after an outage. Low voltage operation is bad for drives, and this is the suspected cause of the drive’s failure.
The solution for this one is simple, when an outage occurs, simply shut off the computers or their surge protectors. After the power comes back on, switch them on again. The neighborhood inrush will only last a couple of seconds, by the time you reach down and flick it on, all should be safe.
A couple more tips while we’re on the subject. Always have a good surge protector on your computer and all of it’s attached devices (monitor, router, printer etc.). Never use your computer during an electrical storm. And buy a battery backup (UPS) if your data is critical and changes often. Should you have any questions about power related problems and how to solve them, call us. We are an IT support company that loves to find solutions to your IT needs.