Source: Microsoft [TechNet]
quote: I can list some off the top of my head that use more than 2 cores.
quote: A game is processor-intensive with a load that cannot efficiently be spread around since a lot of the calculations are intertwined with each other and cannot be split apart, processed independently and returned as they are completed. Even if the load is split, it still needs to be recombined and it still needs to wait on the main thread. This adds processing overhead, increases memory usage and adds a thick layer of complexity to the code among other things.