Power Suply question

[StorM_GmA]

I was curius about how ppl can calculate the Watt needs of their
pcs so i found some calculators on the internet.
It was quick and easy so I tried to make a calculation for my pc.
I was impressed when I saw the result.
about 290Watts! And it was weird because my pc has lot of stuff
on it (drives,hdds,case mods etc) and generaly it's not a simple
pc with 1 cd rom,1 floppy and 1 hdd.
So,i checked my power suply again and it was 400Watts. if that
calculator gave a true result, I don't really need so many Watts.

So,here are my 2 questions:

1) Having a power suply with more Watts than the required can
cause any damage or just the rest Watts stay unused?

2) What attributes make a power suply better than another one
with the same Watts? I mean from technical side... not just a
nice look!

Thanks =)

 

[Ste]

http://www.techist.com/showthread.php?threadid=77323

Section 4

And you only use what you need for a power supply as in watts but its good to have more then you need for heavy load usage and upgradability.


OH and also looks have nothing to do with a good power supply.