Hello!

I'm looking into building an NAS type box. I'm somewhat concerned about power consumption because:

a) I already have a P4 IBM eServer running 24x7

b) I have a number of other computers that are on for extended periods of time (MythTV network)

and

c) I can't find a whole lot of existing information regarding this

So, my ultimate question is:

If I stuff a 600w PSU into a system with identical hardware as a second system with a 400w PSU, will the 600w systems consume more power (assuming the 400w is enough to power the hardware)?

Closer to my actual test I'm hoping someone has done:

Is there a huge difference (regarding power consumption) in using one of the 120w cases PSU's (like http://www.logicsupply.com/product_i...roducts_id/107 ) powering a mini-ITX board versus throwing it into a regular case with ~350w power supply?

Thanks!

Cool

Depends on the efficiency and power factor of each power supply. Computer power supplies are switch-mode power supplies. They consume as much energy that the load needs plus their own energy.

Excellent, I think that pretty much means what I hoped and thought.

Basically, assuming they are equal (in quality and efficiency) a 450w PSU will "consume" the same amount of electricity as a 600w PSU with the same components (assuming the components require far less than 450w of power). Would that be somewhat accurate? I guess the biggest part of your response that leaves me wondering is "plus their own energy". Does that mean that a 600w PSU will still consume more power than the 450w (in the example) simply because it's a larger power supply (assuming all other things being equal)?

Thanks for the response!

Cool