Sandra
While I don't believe the absolute integer results the Core 2 Duo reports in the Sandra CPU benchmark, I think that it may still indicate relative performance; after all, it is running the same integer code!
The E6600 apparently beats the X2 5000+ at stock soundly for integer results, and is in turn trounced for floating point performance. It manages to nudge out the 5000+ for SSE2 floating point.
The overclocked E6600 dominates all the stock results, and the overclocked X2 5000+ results.

The story changes when we get to the memory bandwidth benchmark; the AM2 processor's on-processor memory controller shines here. The overclocked E6600 manages to beat the stock X2 5000+, but the stock Conroe's are trounced by the stock X2 5000+ ... and the overclocked E6600 is still soundly beaten by the overclocked 5000+.

WinRAR
Ok, here the Core 2 Duo's shine... they dominate the WinRAR results.
