2X Graphics cards, which one is used by Final Cut Pro X?

[gnomeisland]

I installed a GTX 570 in my Mac Pro. So far everything works great and it is recognized just fine. I left my GT 120 in there because I have the space and it is the native card.

I know with Resolve/CUDA the recommended set up is run the displays off the GT 120 and use the faster card just for CUDA. Does OpenCL in Final Cut X work the same way? Honestly, I haven't noticed much of a difference in Final Cut (although Lux Mark and other benchmark programs shows a very large performance increase). I am currently still running the displays off the GT120 and wondering if that is the problem.

[linuxcooldude]

Supposedly on cards that use more then 2GB of VRAM OpenCL is not activated. Now with Mac OSX 10.8.3 there is no limit & OpenCl will work with no work around. Not sure if that is your problem or not.

[gnomeisland]

Originally Posted by linuxcooldude

Supposedly on cards that use more then 2GB of VRAM OpenCL is not activated. Now with Mac OSX 10.8.3 there is no limit & OpenCl will work with no work around. Not sure if that is your problem or not.

I don't have more than 2GB on the card so I don't think that that is the issue. Does OS X fully use the card if there isn't actually a display plugged in?

[mjsanders5uk]

I believe Apply specifically recommend only one graphics card on an FCP X system.