The new opteron is basically just a rebadged version of the current San Diego cores, that are used on the A64 3700+, 4000+, and FX 55 and FX 57 these processors use the same cores same everything just different name. The opterons are produced with higher yield silicon therefore they are more likely to hit a higher OC, like the many of 3ghz you have most likely been seeing.
So treat it as a normal A64 socket 939, because thats what it is.