New motherboard is here.
A fresh install of W10, went smooth as butter, finding 2x GPUs, Check, running in SLI, check, running 4 monitors with a daisy chain, Noooooope, instant crash.
This annoyed me, so i started to consider that my VERY pricy Displayport 1,4 cable was the cause of that issue. Hooked up the 4th monitor with HDMI cable, and it sprung into life.
Some how i got hit by 2 seperate issue at the same time via windows update? Motherboard sure as hell had an issue, but also seems like the display port cable has one.
But, so far, so good for the SLI setup. Still need to run more benching and testing, but i think my issues are solved.