new card same game

I recently updated my graffics card from 9500pro to 6600gt. Shortly after, I reinstalled BF1942 to play a quick game( test drive if you will). I was suprised that gaming preformance was not improved noticably. I still got slow fram rates when large number of people were in one area(aberdeen).
So my question is this, shouldn't I get lights out preformance since my new card is 2 generations newer then the game( I think the bad boy card when the game was released was 9700pro). Or is it just connectin lag ( although I have cable). my processor is a little older, XP2500 , but is newer than when i first got bf1942( I cant remember if I had the xp1900 or the thunderbird 950)
any thoughts......

 

How much ram do you have?

 

1GB pc2700 corsair cl=2