Sunday night I told my comupter to shut down, as it was doing so, there was a blue flash, a loud pop, a burnt electronic smell, and a little smoke, then nothing, obviously no power. It all came from the PSU, seems like a fuse blew inside. It was a 550w off-brand and only like four months old.
I was in a pinch for a new one, so I went to best buy and got a 400w Antec (biggest they had). It'* nice and quiet, something the other was not. It was more expensive than I could have got it for on the internet, but it came with a 3 year warranty.

Should do the job, right?

You let the smoke out. Now it'* magic is gone.

Depends on your CPU....but 400W is not bad. As long as your system is running OK you shouldn't have any issues.

Athlon XP 2100, 512mb ddr, two HDD'*, CD-ROM, burner, case fan, Coolermaster Jet7, AGP vid card, wireless card.

Seems to be running fine.

You'll be more then fine. 400w is still overkill.

I saw an online power calculator that suggested I use a 300w minimum, that would take care of everything running at once.

Having W is nice, but my brother keeps saying that it'* the consistent amperage that matters... My 430W Antec should be able to outperform a 550W no-name brand, due to the consistent and reliable amperage...

- I'm still waiting for my Radeon 9700 to come back from RMA, the fan failed... AthlonXP2500+, 512MB Corsair DDR RAM with the LED'*, lotsa case fans, the works... limping on 16MB ATi Rage 128 PCI graphics for now

My computer here at work let it'* magic smoke out the other day. Kinda funny. people still talk about it.

The techs said it was due to dust and overheating. I woulda bet on the snow melting off of my shoes since I use the CPU as a foot rest.