That Sempron may have just been a really good proccesor from the batch and the XP may have just been a really bad one, there's many different factors that you hvae to take into consideration when looking at benchmarks.
Anyways, as you yourself have said, the XP outperforms the Sempron in every other benchmark, so it's obviously the superior proccesor, and I think that benchmark has been flawed anyways.
Intel C2D E6320 / AMD Athlon X2 3800+
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