Here we have the CPU-Z details of our two stars. Unfortunately, our choice of board prevented any overclocking. Even the Intel board didn't allow for much leeway, apart from multiplier changes. The GIGABYTE board wouldn't allow us to raise the FSB above standard; any settings other than stock would cause endless BIOS loops and required CMOS resetting.
So, now that is said and done, we'll have a look at the CPUs themselves. From the data between the two, we can see that both the standard Core i7 920 and Extreme Edition 965 share the same core, only the Extreme gets a 540MHz bump in clock speed. Also, to help get the Extreme Edition further ahead, it uses a 3.2GHz clocked QPI link, while the 2.66GHz uses a 2.4GHz clocked QPI.