Fog Creek Software
Discussion Board

Hard Disk Failure and Power Fluctuations

Joel, are you sure your hard disk failures aren't caused by power fluctuations?

My parents have a home office on the side of their house with bad power and every 6 months their hard disks seem to develop bad sectors and things. This has happened for years now. But a UPS has fixed it.

Matthew Lock
Sunday, January 26, 2003

I don't think so. Laptops use the battery to supply constant power, even when it is plugged in. This is why there is no "kick over" period when you rip the plug out of the wall.

So I would think that any power flux would simply be ignored because the battery compensates for the loss.

Sunday, January 26, 2003

Matthew might have a point.

If your office is in a building which is quite old, cabling and stuff can't be trusted.

Try getting a regulator or a UPS.

Prakash S
Sunday, January 26, 2003

We had to get a UPS for every machine in our office, because of this type of problem.

Sunday, January 26, 2003

Laptop hard drives won't be affected by a power fluctuation but are affected by being moved around.

The failure rate for laptop hard drives is horrendous.

One thing to look out for is A/C's. The motor on A/C units can play havoc with any kind of magnetic storage. There was a famous case of a shop that found itself getting a 30% return rate on floppy disks. When it moved them away from the A/C unit in the storeroom the failure rate returned to normal.

Stephen Jones
Sunday, January 26, 2003

Just to add from my original post, my parent's office's lights would dim each time the A/C started.

Matthew Lock
Sunday, January 26, 2003

Matthew, thanks for the post.  That explains my HD crashing.

I was having a dimming lights problem, then one day the HD motor was clanking loudly.  At first, I thought it was the power supply. 

I put in a new HD (original one had corrupted boot sectors or such, in the Windows system folder, and would start to clank lightly after a while) and one day, the "new" system (new HD) just shut itself off automatically.

I have two computers in the same room at close proximity.  I know nothing about what a UPS physically looks like. 

Can I buy one to back up both computers?
What does a decent one cost?

Brian R.
Sunday, January 26, 2003

Brian, you can use one UPS for both computers. The cost will depend on whether you have two monitors or just one, and how much time you want the UPS to work. If you can afford it, prefer a UPS that constantly supplies power from its battery, rather than one that kicks in on power loss. They're more expensive, but MUCH more reliable.

And, keep in mind that a UPS supplies backup _power_. You still have to backup your data independently.

Ori Berger
Sunday, January 26, 2003

I have a back-UPS Pro 500 from APS. It's a box about 10 by 10 by 6 inches and fairly heavy due to the lead acid battery inside. i paid about $120 for it including shipping.

I would recommend everyone get one of these sorts of things as this has solved no end of problems, despite alllegations that the power here is supposed to be clean and pure.

A surge protector is almost worthless, as is a surge protector with a battery back up. You need one with a voltage regulator as well so that if the voltage drops to 90V or goes up to 145V temporarily, your delicate electronics aren't hosed. Hard drives are the first things to go, especially with low voltages which are also known as 'brownouts'.

This one here drives one computer and various equipment but could probably drive two. You can get them in various capacities depending on how much juice your system requires and how long you need to run it to shut everything down gracefully if the power goes out.

APS also has pure voltage regulators without battery backup, but you have to search their catalog pretty closely to find them.

A/C, flourscent lights, refrigerators, vacuum cleaners, waxing machines -- all these things can hose your equipment. If you have any of these things possibly on the same circuit as your gear, you need an APS and even if you dons't you need an APS anyway. It is an essential part of your setup that can not be neglected.

X. J. Scott
Sunday, January 26, 2003

*  Recent Topics

*  Fog Creek Home