EPThttp://www.newegg.com/Product/Product.aspx?Item=N82E16813131377
It's a P45 so unlike the X48 you picked out, it doesn't support full speed x16/x16 crossfire.
I'd also get the HD4850 because it's the same price as the HD4830 but it does have a rebate.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102824
The E8400 comes with a heatsink so you don't need to buy one unless you're going to do some major overclocking. I'm not a fan of zalman anyways...
The power supply looks ok but rosewill used to be terrible but I hear they have gotten better. I wouldn't risk it though, i'd go with this PC Power & Cooling for $65 after the coupon code. (you could probably find a better deal if you look around)
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703016
dont forget you can get 2.5% cashback from newegg if you go through live.com
http://search.live.com/cashback
If you can spend a little more go core i7, it would be much better imo.
