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Motherboards are going to be the issue in the future. Good X79 boards might as well be made of gold. You can still get a few boards new from Supermicro and ASRockRack for V1/V2 but they are not cheap either. The X9SRA goes for about $270
About these mainboards: I bought a Asrock Rack EPC602D8A some months ago for my E5-1680 v2 because it had some overclocking options. And indeed you can change the CPU multiplier and voltages in its BIOS. The big issue was that I couldn't get the CPU to ignore its 130W TDP limit. There are BIOS options for short and long duration power limits, just like in any other X79 board, but they don't do anything. So under light loads I could run this Xeon at 4.2 GHz (all-core multiplier of 42), but as soon as something more was going on, it downclocked to 3.7 GHz. I monitored the TDP with HWMonitor and hwinfo64, it never got any higher than 132 W. The same issue occured with an i7-4820K in this board, it could never exceed its TDP.
As soon as I switched to an Asus P9X79 Pro, this issue was gone.