FX processors based on Bulldozer microarchitecture managed to show their strengths only in a small variety of common user tasks. There are very few popular applications, which would generate simple multi-threaded integer load and this is the only case when Bulldozer really performs at its best. As a result, in certain applications the new Bulldozer is not just slower than competitors from Intel, but is even slower than the previous-generation Phenom II X6. And it means that AMD didn’t succeed in launching a revolutionary desktop CPU.
In fact, FX is just another Phenom, which looks pretty good especially compared with the predecessors. Overall, FX processors are faster than Phenom II, they overclock much better and consume slightly less power, so they will be a good replacement for the CPUs on old K10 microarchitecture.