Z370 Taichi SLi+Pcie nvme ssd wont work

On previous config i can easy use 2 cards in sli + nvme ssd in third pcie slot.

With my new z370 taichi i cant do this. If i put nvme ssd in the third slot, there no sli option in windows. All is working, but no sli. If i run system without ssd - sli is here.

So, my question here - am i missing any tweak in bios? Ranger viii was working without any tweaks from the box. 

Yes, i see, z370 taichi can run only x16/0/0 or x8/x8/x0 or x8/x4/x4 config. But z170 ranger viii too!!! There same pcie lines management how i can see - 16 lines from cpu and x4 third pcie slot from the chipset. So there no physical limitations to run sli+x4 with taichi. Why i cant do this? This is very disappointed me.

I will be grateful for the advice.