Well, I believe the main reason they say "533/800 only" is because they're trying to make sure nobody is using the old Williamette core on these boards. I'm fairly sure the 2.2 will work, since ALL 2.2's use the Northwood core.
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<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>