Edit3: The AVX version is the same miner compiled to support the AVX instruction set from the newer CPUs. You can check if your CPU support AVX using CPUZ. http://www.cpuid.com/softwares/cpu-z.html. From my initial testing I couldn't find any significant speed difference between AVX and the regular one, probably because the code wasn't written to use it. If somebody can come out with a proof that it's worth using AVX then let us know.