Nice cpu, if you are wanting to be cheap then look at a GTS450/5770 or a used GTX260 however the best bang for buck card out there with stable drivers ect then look to a cheap GTX460. I got one my self and they are dependable.
I have a 600Watt PSU. I play a lot of Company of Heroes on my PC and also other RTS's. I would like to be able to play on ultra settings and do 4v4 games with no issues with FPS. I have no preference for ATI/Nvidia.