Mojave Nvidea GT120

Ok, I tried it, It will not boot into Mojave with the RX580 in the slot and the GT 120 present. It might on its own but not with both so there is a conflict. . It will seize on the start up and not boot. The Nitro has a slot for a HDMI output so my solution is to sacrifice the frame drops and let the Nitro split the memory with a second monitor. I will run a benchmark in High Sierra now. The last I did in Mojave was 60 fps so it is not that far off High Sierras 67 fps. I may just save the GT 120 for emergency boots into High Sierra. Mojave has a multicore advantage and it fixes Harmonys rendering but I lose After FX so Im stuck maintaing two. I think game renders in HS are faster too. Give and take.

I think I may have found the answer. It will indeed run the Nvidia GT 120 even as the main screen . It will be slow but it will run. Now the question is will having that card in affect the performance of the RX 580 Nitro.

https://forums.macrumors.com/threads/nvidia-gt-120-running-mojave.2164967/

Yes, I know, it required I remove the Nvidea GT120 to install it. The question really is once Mojave is installed can you put the Nvidea back in? Has anyone tried it ? Will it hurt the card, will it run? Is there another low power metal capable card that will run the boot screen? Apple shows you how to install Mojave on these Mac Pro's , I'm not sure why Nvidea/Apple would not allow a patch to make a non metal card work. I use it for tools. For the moment I may add two separate backups for the Mojave and High Sierra versions. I need my After FX so it is stopping me from completely converting.

As I mentioned I am running a Sapphire Radeon NITRO+ RX 580 8GB GDDR5 PCI-E Dual HDMI / DVI-D / Dual DP, It is metal capable and works quite well. It did correct the issue in Harmony. Now that was to installed of course there is no boot up screen still.

Just so everyone knows Mojave will kill AfterFX , require you to install legacy Java to run Photoshop etc . The chart below isn't really fair because I ran the Mojave drive off a slower OWC SSD vs a Sandisk SSD of the same size, I was opening and closing things while it ran and Geekbench still finished 30 seconds before the faster drives 3 minute 30 seconds finish with a higher multiprocessor score 26000 vs 24000 in High Sierra. Good things vs losses. Sadly I just got the GT120 and such a great price . It is shiny and perfect.