hmmm alright thanks guys! I know that i really need to upgrade my cpu now. Thanks
I want to get the Q6600 quad core
I'd suggest overlooking the bickering going on and focus on the main points at hand. Your P4 is a bottleneck, no doubt about it. But you will still be able to get some decent fps with the 4870 regardless. The GPU is of course the single most important upgrade for video peformance, and since you've already bought it, go ahead and use it. For good physics oriented games at high res it will begin to show it's weakness for certain. If you look at the article I posted you see that even the E2160 core 2 at stock speed (1.8 GHz) was a bottleneck of 30% compared to the q6600, and this processor (the e2160) ranges from slightly to considerably better than your P4 3.0 Ghz for gaming, depending on the game etc. But an overclock on the E2160 to 2.4 GHz reduced this to 15%, and at 3.0 GHz there was little difference. There is little to no advantage for quad-cores vs dual cores at the moment, but that is changing.
So enjoy it, and plan to upgrade, but there's no sudden impending urgency here.