I tend to look in Wikipedia tables to get the information I need on the processors. In this case, the following table has two entries for the two different "xeon 5300" series steppings (B3 and G0).
https://en.wikipedia.org/wiki/Intel_Core_(microarchitecture)#Steppings_using_65nm_process
An Intel CPUID is composed of codes for Family, Model, and Stepping. So of the two CPUs, the CPUIDs are:
06F7
06FB
B is hexadecimal for 11. Looking at the stepping column for that row is G0.
Now maybe that's a huge coincidence, so I then searched for (not sure exactly), something like "stepping 11 G0" just to see if I could find them together anywhere and found this, which seems to confirm it:
https://serverfault.com/questions/3...-betwwen-two-xeon-cpus-with-stepping-11-and-7
I sure hope somebody actually makes use of this information some day.
But I don't mind spending the time--I find it to be interesting.