[Solved] upgrade from 10.9.5 to 10.10.3 -> displays not detected

[tonyvm]

Hey there, been a while...

I finally updated to Yosemite today, did a clean install on a new SSD, and it went very good, thanks to the installation guide on this site.

I have a TV connected to the hdmi port of the motherboard, that's what I used during installation.

Everything went fine except for the 2 Apple cinema displays that are connected to the GTX780 are not detected anymore. I installed the updated Nvidia drivers but still nothing showing up in System profiler, except the GTX780 itself. NVIDIA web driver is selected in preferences.

Been searching the forum but no luck, any ideas what could be going on?
It's still working fine when I boot 10.9.5.


UPDATE:

FIXED: system definitions 6.1 was causing it, now on 3.1 and working!
Could not using 6.1 be a disadvantage for using 2 GPU's?

 

[Stork]

upgrade from 10.9.5 to 10.10.3 -> displays not detected

...Could not using 6.1 be a disadvantage for using 2 GPU's?

No, it shouldn't since the Mac Pro 3,1 could run two graphics cards.

 

[slim.jim]

upgrade from 10.9.5 to 10.10.3 -> displays not detected

To elaborate on the 6,1, the drivers don't load when using a iMac15,1 or MacPro6,1 system profile so the display shuts off right before it would show the login screen or desktop. It can be fixed however with a plist edit.

 

[tonyvm]

Could the MacPro6,1 system profile help on power management?
My overclock to 4.5GHz isn't working anymore and Final cut pro x seems slower with 2 GTX780's instead of just 1.


UPDATE: overclock solved, forgot to delete NullCPUPowerManagement.kext
2 x GTX780 issue unsolved

 

[toncij]

To elaborate on the 6,1, the drivers don't load when using a iMac15,1 or MacPro6,1 system profile so the display shuts off right before it would show the login screen or desktop. It can be fixed however with a plist edit.

How could that be fixed, please?

 

[slim.jim]

How could that be fixed, please?

http://www.tonymacx86.com/graphics/161439-gtx-970-black-screen-after-nvidia-346-01-02f01-2.html