The corsair PSU will likely have one, maybe two strong rails to deliver all that power, meaning you don't have to worry about what plugs you use on the PSU. Also, the Corsair PSU comes with a better warranty and will actually output 450w, and do so while being efficient (the 80+ rating). The no-name PSU would possibly not even be able to output 450w, and if it did it would be dirty power (makes overclocking unstable, harder on components, etc) and not very efficient. Also, cheap PSU's have a tendency to fail spectacularly and often take other components with them.
I wouldn't skimp on the PSU, as a good one can last many builds.
Something like this would be about the minimum I would personally be comfortable with.
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Something like this might be worth the few dollars more though, to give you a little more wattage breathing room for upgrades down the line:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182200