Interesting findings, I'm going to test it more on my config with memory set to 1833MHz and 1600MHz tomorrow or on Sunday.
If you have time to test cgMiner for me then below is all you need to run it. Just start Kaveri.bat and let me know if you will get any HW errors.
https://www.dropbox.com/s/evgtfegaca....2-windows.zip
In bat file you can play around with Thread concurrency and values up to 12200 should work and you can try to remove --no-restart from bat but on my motherboard it causes blank cgminer window (on Gigabye and 5800k it wasn't needed and it's to do with GPU FAN monitoring).