Personally I always felt that duals cans give you a slight advantage in gaming. This is b/c one cpu can work on the OS while the other is left to run the game. Although I doubt you will really see any major performance differences. One fast cpu is better than two slow. (gaming wise). But if you have two fast thats always a plus.
Well I have NOT yet run in to a game that I have had problems running with my dual PIII9333 and Geforce3 card !! But don't buy a dually because you expect to get better gaming performance, get it because you like the fact that you can run several other CPU intensive programs WHILE gaming
yeah thats cos most games programmers have such ridiculously tight milestone deadlines that they haven't got the time to implement the proper multithreading that they'd like ..they're all on to get the damn thing running at all to save the bloody marketing department bleating.. umm sorry .. involuntary rant..
oh and some are too incompetant .. heh