It looks like memory to me.
1.First make sure you have the latest bios settings installed.
2.Make sure that the memory you are trying to run is supported by ASUS : https://www.asus.com/Motherboards/ROG-MAXIMUS-XI-EXTREME/HelpDesk_QVL/
3.Check if the ram stick are insalled in correct slot, I think on default it's 1 and 3, don't quote me, check manual.
4. You can also try to run them in 2 and 4.
5.If you are running 4 memory stick that that might be your problem, try running only 2.
6. I had a 4500 Mhz Corsair that was supposed to run on Maximus XI Gene, but I couldn't get it to run anything above 4400, so instead of trying to force XMP, try to do it manually, leave the CL timing a per spec but reduce the Mhz to lower value.
7. Basically I should have started with this : make sure it runs straight out of the box without XMP settings. Default or on auto or whatever is the case.
Hope this helps.