Simple yes or no question:
Does every X79 board work with 2011 Xeon chips?
e5-2670 will work on most x79 mobo's; be sure to check google with your motherboard if they support them.
Ivy xeons (which are very expensive) will also work if it supports normal xeons. There hasn't been much changes.
There's no point in getting ES xeons, sandy based xeons are very cheap under $60/cpu.
OK, I was just wondering because with the 2670s around there are not many options to use those in single CPU config. The boards on the X79 are to expensive. But I might have found an option for that:
Intel X79
4 Dimm slots (no ECC or registered though)
500W PSU
Integrated cooling
Would be interesting to see if these work.