hey, if your keeping you motherboard which will be a am3+ board, id go with a fx6300 or if you can afford it jump to the fx8xxx 8-core range.
the fx6300 is 3.5ghz at stock but overclocks so easily to 4ghz+ without a sweat. its only around £70/£75 i believe aswell. got to be one of the best 6core amd processors for gaming too!
as for your graphics card.....what budget do you have and what psu do you have?