Wattage is way over-rated for power supplies. Quality and amperage is what you need to be concerned with. As stated, a roughly a 500w (ar 40 amps or higher) will run that without problems.
What's more confusing is most power supplies will tell you a wattage rating and it's the total power deliverable by the 12v, 5v, and 3v rails. The good ones will tell you a wattage and it's the deliverable amount by just the 12v rail (the important one btw). Meaning that the latter example delivers a total power output well past the number of watts advertised. Only way to differentiate what's what is to compare amperage output with same-wattage units. Get something with 40 amps or higher and you should be set for most anything short of a high midrange SLI/crossfire GPU set up.