I'm not sure if anyone is aware of this, but the motherboards that fullzero lists are all intel motherboards.
If anyone was wondering though, I have a MSI 970A SLI Krait Edition AMD motherboard and an Athlon II CPU and I got fed up with ethOS, so I gave rxOC a shot.  I can confirm this works with 4 GPUs.

by the way fullzero, thanks for nvOC and rxOC.  Amazing work!