For gaming, the most comparable CPU to the FX-8320 in performance is the i3-4330.
Of course, there are a few random games where a Pentium beats the FX-8320, and a few random games where the FX-8320 beats a low-level i5. But those are outliers. Usually an FX-8320 will perform about the same as an i3-4330.
for gaming, which has variance, i3 or i5... but generally the i5. For specific tasks like rendering and video encoding and physics based operations (3d renders) the 8 core FX sits between the i5 an the i7, and often closer to the i7 than the i5.
probably the 4570 or the 4570k they are a little bit more expensive but they do run a lot cooler or you could go with the 4670 or 4670k but the 8350 is a very good budget cpu especially with its overclocking capabilities
*It's not easy to compare if you're talking GAMING because games vary on how many CPU cores they can effectively use. For a game like BF4 you might see little CPU bottlenecking but for a game like SKYRIM you might see about 40% better performance using a modern Intel i5.
If it was comparing something basic like video converting with HANDBRAKE that would be very simple.
For gaming, the most comparable CPU to the FX-8320 in performance is the i3-4330.
Of course, there are a few random games where a Pentium beats the FX-8320, and a few random games where the FX-8320 beats a low-level i5. But those are outliers. Usually an FX-8320 will perform about the same as an i3-4330.