Two video cards , need to disable one

[Blacky]

So I got this working for me:

http://www.insanelymac.com/forum/topic/327022-nvidia-oob-for-2-x-4k-60hz-displays/

 

Everything worked fine with both cards until last month when I scratched my GTX 760 ITX and had to buy a new.

 

Today my new GTX 760 ITX arrived and I installed it, but my system no longer boots into macOS.

The only way to get it to boot is if I completely remove from the slot the GTX 1080. I tried just removing its power cables but still MacOS won't boot.

 

Everything is fine as long as the GTX 1080 is not present in the system. If it is I get this error:

IOConsoleUsers: gIOScreenLockState 3, hs 0, bs 0, now 0, sm 0x0

H000-A newUserClient failed: 0xe00002cd

 

Any ideas?

 

Thank you

 

Edit:

I think the issue might be related to the PCI order. Though I don't remember changing it.

I get:

GeForceSensors (pci2): VBIOS successfully read from PROM

GeForceSensors (pci2): chipset: GP104 (NV134) bios 86.04.17.00

GeForceSensors (pci2): started

GeForceSensors (pci4): VBIOS successfully read from PROM

GeForceSensors (pci4): chipset: GK104 (NVE4) bios 8-.04ea00

GeForceSensors (pci4): started

[Blacky]

I wasn't able to disable either of the video cards no matter what I did.

I tried installing Nvidia Web Drivers and seems that the system is now booting fine.

 

There seem to be some incompatibilities with the native support for the GTX 760 and the existence of other GPU adapters on the system.