I'm fairly new on this site and I see where a lot of you worry about power spikes and outages. Just about everyone has a sruge protector but it seems as if no one has a power back up system. I have two computers and both of them are on aN APC Backups pack. They allow me enough time to turn off the computer properly. For the cost of a mobo and precessor you can afford one better than the lost of data or your whole system. Also they can act as a filtering device if you go on generator power during a power outage.
And with all the LCD and plasma tv's today, they could save you a lot of money. www.APC.com has all the poop on them and they have a great warranty on them to boot.

The "Backups" is called a UPS, Uninterruptible Power Supply.

Care to tell us how you determined the proper Volt-Amp size you needed for your computer?

Sorry DCC, but it is APC, Ijust looked at mine to be sure. here is a little electronics lab for you.
P=power in watts
I=current in amps
E=voltage in volts
R=risitance in ohms
ok if you know the rating in watts of your power supply, and you know the voltage you would use I=p divided by e answer will be amps. Lets say you have a 500w psu and you are useing 115volts you divid 500by115 and you get 4.34amps and that will tell you what size to get .
If you really want to get into the formulas used in electronics go to ask.com and put in "electronic formulas and you will a whole page of them. I had forgotten so many of them that I had to go look them up.:)

APC is the manufacturer, UPS is the product.

Ohm's law is useful only if you add all of the combined wattages of the combined devices.

You'll right DCC about the name and and product.
To determine the size you would need is to add up the current ot the items you want to attach to the unit.The one I have has two plugs on the battery side and three plugs on the surge side. My computer and montior and computer are on battery, my printer is on the surge side. It gives me about ten minutes to shut down. The wife's unit is a bit larger and give her about the time to shut down.
When I got this machine back up a couple of years ago, I brought a refurished unit for less than 50$.
The APC site has a page that can help you on making a chose on size.With just montior and Computer using it the best one they advise is less than "c" note.

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