Make sure BIOS is 4502 or recently released 4608. I just did a complete build with ASUS Sabertooth X79 and I went with the i7-4930K since ASUS site said it was supported, Intel site in Dec2013 still did not list supported mother boards. They just recently listed some.
What RAM are you using?
My only issue so far is the RAM and memory error when running XMP/1866Mhz but I do not have any issues untill in Windows. At this time it gives the 1 beep tone followed shortly after by two beep tones in Win8.1. I originally started with the ASUS QVL listed Corsair Domminator 32GB (4x8GB) quad channel set and really had issues in 1866Mhz XMP or Manual. Luckly was able to RMA those and tried the Corsair recomended Vengeance 4x8GB (CMZ32GX3M4X1866C10R) 10-11-10-30 set and so far, I only get the tones in beginning of running tool to stress it. Seems like I can run it for hours and not hear the auditable warning tones untill next day. Runs fine in 1333Mhz with no auditalbe tone errors for memory! Still hoping this is just a New CPU issue with BIOS, it has not failed any testing tools and have not found any errors in Windows logs.