The two boards I bought from a decommissioner, had 3960x in them, and 16gb Corsair Dominator 2133 DDR3. I kept the ram in my Rampage 4 extreme. One of the CPU's would BARELY boot to windows, and then freeze... the other ran the IPDT just fine.
If you google... "asus p9x79 WS/IPMI Bios Files" it should be the 6th post down, from a site named rebyte. Unzip the file, put on a USB stick. You'll need to clear your cmos, then with USB in, boot, and use the in-bios flash tool. No need to rename, or anything. That gets you to version 1208 bios. Note** I had to manually download it, then right click and save as, the downloader they had wasn't sending the file for some reason.
Then, the aux 2 connector, on the row CLOSEST to the white front panel connector(power, reset, speaker, HD/IDE led..) there is one pin, then a gap; you need to put a jumper across the 2 pins right after the gap. Do that before you update the bios, AFTER you have reset the CMOS, and you should have no issues. I have TWO of these working for me, and albeit a 6 hours grind last night to get the first one done, and functional; it does support win10, GTX10xx cards, GTX 9xx cards and I would imagine the 16xx cards as well, the same as my Rampage 4 Extreme.