You don't really need a lot of watt for that machine, 400-450 will do just fine, just get a nice bronze certified one and you're pretty much good to go

Or just get 500/550W so you won't fear future upgrades, otherwise 450W for that config will do just fine. pretty much any Antec, Corsair, Xfx, Cooler Master, you should be able to find a nice ass 550/600W psu with that budget

be quiet.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151094&cm_re=seasonic_psu-_-17-151-094-_-Product
Bam, you can go higher wattage if you want.

Here's a very thorough review of it.
http://www.jonnyguru.com/modules.php?name=NDReviews&file=print&reid=185

ye just go for this, it's great

Personally I love the corsair CX600.

Solid stuff and leaves room for upgrades as well.

If you want a decent quality power supply, I implore you to check who the actual manufacturer(often listed as the Original Equipment Manufacturer) of the power supply series is. A very large portion of PSU producers don't actually make the PSUs themselves and will use units from various manufacturers. This means that you can get great variety in quality between series of the same producer; some of them actually use this as a marketing tool by using very good and expensive manufacturers' units for their high-end products and lesser quality, cheaper units for their lower-end products. This way they can still have a good name(most of the press is usually focused on the more expensive products a company sells), while cutting costs on the bulk of the products they sell. Conversely, some very cheap power units made by primary and secondary producers you've never heard of might actually be really good, but this is always a bit more risky if you don't know anything about said producers.

I have personally always used PSUs manufactured by SeaSonic and have never had any problems with them. They also supply a lot of units to Antec and Corsair, but just check who the OEM is before you buy anything sold by a secondary manufacturer. Also, if you're charmed by "be quiet" brand PSUs it is even more important to do this check, as they have an enormous disparity in quality between different models within the same product series, which is very peculiar... especially since they are quite a large and reputed brand; other companies in the same quality tier tend not to do this.

Hope that helps.

Seasonic and Enermax, but mostly the first is unquestionable, also CWT makes decent PSUs

entire CX series except the 400 is made by CWT, pretty cheap quality Twisted tbh, CWT doesnt care much for their lower end stuff

ye sorry i should've specified i was talking about mid-high level PSUs, CWT is sh** when comes to low level stuff