If you got the Sonata II, it comes with a 450w power supply. http://www.newegg.com/Product/Product.asp?Item=N82E16811129155 you said you were looking at the Sonata. I put like a 3700+ machine to gether in it. I didn't overclock, though. But I think it looks like a good value.
this is the slk3000 looks pretty nice but only has one 120mm will that be neough to keep it cool?or is there a fan in the front i cant tell..i think it would be smart for me to get the ocz powerstream 520w. i have one now in my computer and it works amazing.
and with the memory isnt ocz memory awesome or should just go with a lower end cosairs?
I got this case http://www.newegg.com/Product/Product.asp?Item=N82E16811208008 in the silver version and i really like it. The psu is trash but since your going to get the powerstream which is one awesome psu (mines not working right though) you should be good. If you concerned about cooling this case has got two 120mms and and 80mm. Like i said, since your going to oc, dont buy high performance.