FX Series

They are not bad for gaming at all. It's just that Intel CPUs are overall better, but more expensive CPUs.

Well the i5-3570K is the same price as the 8350, so it's a stretch to say Intel is more expensive.

The Ghz rating is just a measure of clock frequency, not the ability to perform work. Just like two cars with a 3L V6 engine may have vastly different torque and horsepower ratings. Intel has a more efficient architecture that gets more work done at the same frequency.