If you success to boot and work some benchmarks than CPU is probably OK, and board maybe need little work...
Did you tried to clear CMOS and different BIOS versions? Last is some 0502 Beta, If you success to boot and enter in BIOS try previous version 0401.
You connect both CPU cables 2x 8pin?
Sometimes board stuck like that and not react on BIOS updates, you update but problem stay, like you did nothing.
I would try to disconnect all cables, clear CMOS and reflesh BIOS 0401 or maybe even previous version with ASUS BIOS Flashback.
For that you need only mobo, PSU and USB Flash drive... You don't need to enter in BIOS - VGA, CPU or RAM to change BIOS version on ASUS mobo, that;s one of reason why I like ASUS board and that function saved me during X99 build. With different board I would probably RMA board and technical support will fix and back me board after few weeks.
http://event.asus.com/2012/mb/USB_BIOS_Flashback_GUIDE/http://event.asus.com/2012/mb/USB_BIOS_Flashback_GUIDE/I have some rule to avoid BETA BIOS except if some problem force me to try him or if BETA BIOS 100% fix some known bug or issue, just like that from stable on BETA BIOS no.
I have stable system almost 3 year with second BIOS for my board, after that I download 15 version but didn't update.