The major conclusion, which we can draw as a result of this test session, sounds as follows. Even though Athlon 64 processors have internal architecture very similar to that of Athlon XP processors, they still differ from their predecessors quite significantly from the practical point of view. We can’t give you a definite answer to the question, if Athlon 64 has become any faster than Athlon XP. In fact, this is just a different processor.
Moreover, there is also not much we could say about the performance of Athlon 64 in 64bit applications or at least in 64bit operation systems and 32bit applications. Supposedly, x86-64 will ensure a significant performance improvement, but it is also quite possible that x86-64 will not receive a warm welcome from the software developers. AMD has already tried to promote its own instructions set a while ago, and this experience could hardly be regarded as a success, to tell the truth. 3DNow! instructions set failed to become widely spread even though it proved to be very convenient to work with. So, we can only wait here for the first signs for or against these suppositions.