This morning the power at our home offices flickered. It was probably related to snow, rain, wind, or other drizzly weather event. Welcome to Spring in North Idaho. But we weren’t worried about our computers because we each of our computers is attached to a UPS. No, I don’t mean the folks in the big brown trucks, but rather an uninterruptible power supply.
Most people have their computers plugged into surge protectors. Although surge protectors can protect your computer from big power spikes, they don’t protect your computer from the opposite problem, which is called a "brownout." Brownouts or "voltage sags" are periods of low voltage that can cause lights to dim. For example, do your lights dim when the air conditioning or refrigerator kicks on? Computers really hate that. They like extremely "clean" and consistent power. Brownouts and other power fluctuations can damage your hardware and cause data loss.
A UPS provides a continuous flow of power into your computer system. They generally have a battery, which gives you enough time to shut down your computer if the power goes out completely. Instead of just warning you when the power is outside of the normal voltage parameters, more expensive UPSs also actually filter the power coming into your computer, so the computer only runs off the "clean" power coming from the UPS’s battery. These units eliminate problems from "line noise" (random voltage fluctuations), which also can cause you to lose valuable data.
When you invest in a UPS, make sure to get a large enough one to protect your system. Look at the back of the CPU, monitor, and other components you want protected to find out their wattage consumption. Add up these numbers and get the right size UPS. For example, I had to upgrade to a larger UPS because I use a 21-inch monitor which draws a lot of power. (Overloading a UPS causes it to beep incessantly, so you’ll quickly know if you added wrong.)
If you value the investment you’ve made in your hardware and data, it’s worth looking into a UPS. American Power Conversion makes a line of well-regarded UPSs. Their site at www.apc.com can be a good place to start your UPS research.