Resolved macOS High Sierra on cMP2009 issue

[RickyHunter]

Hi.
Yesterday I've installed High Sierra on my cMP2009.
Firtly I've tried with the patcher, spent nearly all the day making tryouts but the installer kept on freezing at the end of the install.
Then I've upgraded the firmware so I could install it in normal way: through app store.
To do that I've used my old Radeon Graphics card (Apple original, 4770 model if I'm not wrong).
System worked flawlessly until I inserted the graphics cards I'm using normally (2xQuadro 4000 mac version) and the Caldigit Fasta-6GU3plus pcie card. After the user login, the system opens but it's coming back to the login window in an infinite loop.
First of all: I'm using 3 monitors.
My first attempts were (after I've disconnected everything, putting the keyboard cable into the rear usb socket and using a bluetooth magic mouse):
detaching one monitor: same issue
detaching two monitors: system OK
changing monitors positions on cards: same issue if more than 1 monitor.
Booting back into 10.11: works perfectly as usual with the 3 monitors.
Have you got any ideas?
I'm going to detach also the Caldigit but I don't think it's going to work...

 

[bsbeamer]

Caldigit Fasta-6GU3plus pcie card

Remove this. Major issues after 10.11 or 10.12 with this card.

 

[RickyHunter]

Remove this. Major issues after 10.11 or 10.12 with this card.

I detached it. Same issue, so it’s not its fault. Other ideas?

 

[bsbeamer]

Use only ONE GPU to troubleshoot. Make sure it is powered properly and make sure it's a supported GPU in High Sierra. Multiple GPUs from different manufacturers (especially NVIDIA & AMD) do not mix well in modern macOS environments.

KEEP THE CALDIGIT REMOVED FOR NOW. They're notorious for poor support on newer OS versions. They work like a champ in the OS release they were purchased for/during, but after upgrades things almost always happen with them. It's not just their PCIe cards either (which they've 100% stopped making). Loved their HDPro storage solutions, but never again with them after they abandoned those investments.

 

[RickyHunter]

It seems I have solved this issue even if I think 10.11 works better (with these graphics cards).
I have installed the upgrade to the OS, so now it's 10.13.6 (17G8037).
Then I have upgraded the Nvidia Web Drivers to the latest ones (387.10.10.10.40.131).
Now the system works and each monitor is fine.
I'm noticing only few glitches moving windows. Now it's a fresh install, so last word will be installing all the software I usually use (like Adobe).
I'm going to update if I notice any changes.

PS: Caldigit it's working and it seems to work quite well (I've tried blackmagic diskspeed to test it).