Update!
After much trial and error. It turns out if you space your risers evenly across A B and C it will run very smooth; i had A filled up with 7 cards and B had the other two. Now i have 3x 1060s on Pci-e lanes A 3x on B and 3x on C

Works like a charm i hope this helps anyone else that would be having these problems!

Ive tired hooking up the 4pin molexs to the board but doesnt help anything. From what ive read if you have powered risers ( witch i do) you shouldn’t need to hook up the Molexs. Is that right?

I’ve been unable to install older drivers in ubuntu it just keeps pushing me back to nvidia-driver-390

Someone suggested if 4G encode was on witch it is.

And the i3 7100 can handle up to 16 pci-e lanes according to intel

Still can’t figure it out! :/

Hey everyone im having trouble booting into my system (black screen) after adding a 9th card to the rig im using:

Ubuntu mate 18.04

120gb ssd

B250 mining expert

Intel i3 7100

2x 4gb ddr4 ram (8gb)

Evga gtx 1060 3gb x9

Everything is fine til i put the 9th card on...

Now i have reinstalled ubuntu without the drivers and it boots up but as soon as i install nvidia-driver-390 or the headless version and reboot  the system doesnt boot up just get a black screen again.

Any ideas on what this could be? I’ve refered to this topic where someone was running 12 titan xps before but to no avail:
https://bitcointalk.org/index.php?topic=2750990.0