I am going to buy a case soon but am not sure whether to buy a case without a PSU or the same case with a PSU. The case is the Sunbeam Transformer and comes with a 450w PSU for 90$ (http://www.newegg.com/Product/Product.asp?item=N82E16811166015) or without one for 82$ (http://www.newegg.com/Product/Product.asp?item=N82E16811166005). If I get it without the PSU I will probably get http://www.newegg.com/Product/Product.asp?item=N82E16817148027 a 500w PSU. I am on a budget, so can someone tell me if it would be worth spending the extra $ for a case with the PSU or even more money for a seperate PSU?