How to calculate minimum power supply size

[btims]

I regularly build office machines for my wife's company. I try to reuse existing equipment whenever possible (mostly floppies, Hard disks, and cases). When reusing a case, I have to guess if the power supply is strong enough to handle the new motherboard/processor I'm going to stuff in the case.

Can anyone suggest a way to calculate the minimum power supply I need for a given processor/MB/video?


Thanks


Bill

 

[Onus]

Many of us use the PSU sizing calculator available at: http://www.extreme.outervision.com/psucalculatorlite.jsp.

Keep in mind when you re-use a case, that the PSU with it may not be capable of putting out any more than 50% of its label claim without choking, smoking, and croaking. Fortunately, the power requirements of most business machines are very low, so a "500W" PSU that is really only capable of 250W may work fairly well.

 

[btims]

Thanks for the response, this is exactly what I was looking for.


Bill

 

[marshmellow1991]

I just did that calculator, and it said i should have a 365 watt psu... e8400, 2 sticks of ram, 4870, 1 hdd, 1 dvdcombo, 2 led fans 1 120mm fan and 1 240mm fan with a card reader....o.0