From the description, all looks OK, except for possibly the cpu.
Do you have a link, or the brand/model.
The last place to economize is with a cheap psu.
It will not deliver advertised power, and can damage anything it is connected to if it fails.
Here is a tiered list of psu's. Pick a tier 1 or 2 unit. You need at least a 500w unit with two 6 pin connectors. http://www.eggxpert.com/forums/thread/323050.aspx