To Blade148, Mine did the same thing and I goofed up some of my settings while trying to OC and decided to reflash my bios and when I did it started working on it's own.
I leave the NV Lan setting on auto.
I have done so many adjustments that I can't really recall exactly what made it work but I think it was the reflash of the bios that did it for me.
Couldn't hurt to try.