I have this board + i5-6400 running El Capitan 10.11.5 but I'm using the onboard Intel HD530 graphics (for now).
Using MultiBeast 8.2.3 here's what works (for me), using the UEFI Boot Mode:
USB - all working.
Ethernet - use Realtek RTL8111 v2.1.0d1
Audio - Should be ALC887 and there are 2 options to install. Neither option will give me a device showing up in the system. There is a thread elsewhere about disabling Sytem Integrity Protection (SIP), installing the codec, then re-enabling SIP but with mixed results. My patience is wearing thin and this build is for music primarily, so I'm going to get a USB sound card.
The HD530 onboard graphics do not wake the monitor up from sleep on the HDMI port I am testing. The rest of the computer wakes, just not the monitor. Apparently, the fix is to get Nvidia graphics card as they don't have sleep/week issues, so bye-bye on-board graphics...