computertech82 :
The cpu is fast enough. I played gta4 with a AMD x2 2ghz cpu with a 5830 video card = over 30fps on very high settings. But your video card is far too slow for it. At your lower resolution, something like a 5770/7660/7770 or better would allow it to be playable on your system.
erm no you didnt. not smoothly at least. i tried to run it on a amd athon x2 6000 paired with an 8800gt and got nowhere near playable frame rates. yes the added memory on the 5830 would hgelp with draw distance but the program is so badly ported it just doesnt work well at all on a dual core of any kind even 1 with hyperthreading...
my guess is you so used to poor fps that you didnt notice the slow down or your monitor has a very slow response time which would help in some cases to smooth out frame pacing.
sorry to call you out on this but i see it to often on here... 2.0 ghz is below minimum spec for the game by some way so that and my own experiance tell me your exaggerating... but feel free to prove me wrong by linking me to a 30 second fraps of you playing...