eh, P4 is a decent chip. it will bottle neck the GPU a bit but in the end a 560 is not that high end or that expensive of a card anyway.
do you ever plan to move this card into a new machine in the future?
I plan on using this card on the current rig, then upgrading the mobo/processor as a combo later. After that I will probably switch to a higher end card. I am now looking at a used 5770 on Amazon because it is $50