The amount of cores is extremely important when you working with multiple processes or multiple threads. And the reason isn't terribly complicated. Though it's possible that a single core processor could be faster than a multi-core processor, in the real world benchmarks of multi-core processors of similar product lines are always faster. In other words, double the cores, and roughly double the performance. Same reason video cards are fast. The amount of cores matters. There's a reason pretty much all "gaming" machines have at least quad core. It's not a superstition.