Not all cores are the same:
None of AMDs CPUs and APUs are hyperthreaded, so one thread per core. And the thread is what takes data to and from the core. On the other hand, some of Intels CPUs are hyperthreaded so they have two threads going to each core. I really like Linus' analogy for this, so click here for the video.
The clock speed is not everything:
So if you have a quad core that runs at 3Ghz and you are comparing it to a dual core that is running at 4Ghz the quad core will still probably win, with some exceptions. But if you take that same 3Ghz quad core and you overclock it to 3.4Ghz then the overclocked CPU will win.
CPUs and their chipsets:
So your CPU is a processor by itself and the chipset is a processor that is on the motherboard.