The optimal number of GPUs for Asus B250 Mining Expert

asus-b250
#1

Hello,

I’m trying to compose my cards in this motherboard, but have some troubles.
I saw screen from this forum where 14 RX580 were mining with this board. Also i found info from official site https://www.asus.com/ru/support/FAQ/1034921 where different types of cards are mixed. And screen which x1 should I use for stable work (also i know about GEN2 speed, but is it for amd cards?)

Now I have:

16pcs GeForce GTX 1070 8119 MiB · Gigabyte
16pcs GeForce GTX 1070 Ti 8119 MiB · Gigabyte
16pcs Radeon RX 580 8192M · Sapphire
16pcs GeForce GTX 1070 8119 MiB · MSI

And they work stable at 8 rigs with 8 cards with no B250 Mining expert. I want make some optimization and try to use B250. As i understand there are no problem if you have lots cards like p106-100 1060 (mining edition without video input), but all my cards are having. So i chahge one motherboard to B250 in rig where 8 GeForce GTX 1070 8119 MiB and now trying add another GTX 1070 8119 MiB(both Gigabyte and MSI, also 1070T) but x1 show red during startup. After changed lots of risers i have 9 GeForce GTX 1070 8119 MiB but it is not stable (risers were teken from stable rigs)

So which optimal combination for this motherboard using this list of cards? Which max count of one type, especial for Nvidia?