If your dead set on NVIDIA, I would maybe save $25 a week for a month, get your extra hundred and purchase the GTX260
The HD4850 is a better bang for buck, but we gotta respect what your prferences are if you feel strong on some of your choices. (thats why i didnt change your case in the build I did for you). We build machines to get what we want but we need to make compromises and sacifrices in order to fit our budgets
Maybe you should start fresh and do a new thread title GTX260 build 800 dollar budget and see what people come up then. The card (right now) is only $255 on newegg right now, thats only $80 dollars more. Following helios build below, if you can tolerate that case, do the following to save roughly $80 and you can at least get a machine that has enough horse power for a modren mid grade machine
(I would considered an 8800gt a budget card right now)
Get the E8400. Its 3gz. Your games will run fine. Buy the retail. Drop the aftermarket coolers. this saves $47
Cut your memory in half. Yup, were nickle and diming to this point. You dont NEED 4gb (shows up as 3gb's anyway under 32bit xp or vista) that saves $40 .Can always add too it later too.
Now you have a machine that exceeds the performace of an hd4850
(a 2GB system with a GTX260 will FAR out perform a 4GB system with an 8800gt)
get the Q6600 if you want to brave overclocking (adds a few bucks). I do have to say, that would not be my first choice in a case, but I'd rather have a nice performing rig than a pretty one.
I have this one (
http://www.newegg.com/Product/Product.aspx?Item=N82E16811119137 ). But darnit that puts us $15 over budget again (this case has way better cooling than the other one, and you got a very nice hot card in there to think about)
I hate to play with anything else because it would make your system less durable. I guess you could pick a cheaper motherboard, but I helios is right, that is a very well built mommy board.
spunks