A message of advice resuming all of the below: if your interested to buy one of those extreme processors for LOMAC...dont bother.
I ran a series of tests today with my rig to see what kind of perfomance I would get from buying one of those top of the line processors running at stock speed rather than my "inexpensive" (comparatively) Q6600.
I uped the FSB to 333Mhz (1333Mhz rated) and had the CPU cranked up to 3 GHz by keeping its stock multiplier of 9 (you can lower it but not up it) setup voltage at 1.35V just like the Qx6700 (QX6800 uses same because its better silicon). It will run at 3Ghz for 1.3V but its only stable at single threaded apps, it will hang on multi threaded, so I mimic the Qx6700 voltage specs and it runs just fine.
The pics below show some differences between Q6600 stock and my "simulated" Qx6850 (wich intel will never release):