AMD in the past said that the FX is diffrent the the Opteron how ever most people here agree that the FX is the same thing as the Opteron only with the highest clockspeed. The Athlon 64 is just the FX with single channel memmory how ever the Athlon 64 will be the same as the FX as soon as the 939s comes around only with half the L2 cash.
Best gaming AMD processor right now is the Athlon 64 unless price doesn't matter (3000+ is like 200$ how ever th FX is 750$ and only has a small lead over the 3000+ not really worth the extra cash unless you are a extream overclocker as the FX is easy to overclock and gives great results if extream cooling is used)
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