Here's a site that offers a variety of power supplies:
Using the information that you gave us I came up with a minimal need of: 424 Watts using the following web-site:
http://www.jscustompcs.com/power_supply/I would recommend going to the site above and putting in everything, as I do not know everything that is installed on your system.
You can find quite a few different p/s here:
http://www.tigerdirect.com/applications ... ?CatId=106In terms of selcting one I would recommend going for the 600W one if money is available. If not I suppose a 500W one would work, and 550W would be better...
As a matter of personal preference I would like to get one of those modular ones as I don't sue all of the connectors that I have on my current model, so next time it I need a new one I'll swap over to the modular 600W more than likely... ;-)
Hope this helped..
Jared