Originally posted by: LoneNinja
Look at GTA 4, its extremely quad happy. I know someone with a Q6600 that's messed around with it, claims the game runs better with his Q6600 down clocked to 2.0Ghz than it does with it overclocked to 3.0Ghz and affinity set to utilize only 2 cores.
I also know that Left 4 Dead runs better with a quad than a duel, although its difference isn't nearly as great and even a good single core is still capable of running that game. The Unreal 3 Engine and games based off of it also make some use and show improved performance on a Quad vs a Duel.
Currently a good duel core will run any game, but its only a matter of time until the majority of new games are quad threaded.