I too am having a primary/secondary graphics card issue.
I have two graphics cards installed, a GTX 760 and a Quadro K600. the gtx 760 is configured as the primary graphics card yet lightroom insists on using the quadro, ( a slower card ) for the GPU acceleration.
For me, it is not acceptable to disable the quadro in order to get the gtx 760 to be the GPU accelerator.
Is there anything in the works to be able to choose from the preferences performance panel which GPU to use? Photoshop picks the correct GPU, so why doesn't LR???
Thanks in advance.
I deactivated my Intel HD 4600 driver to make my GTX 765M my primary GPU in LR CC - but now PS CC complains that it won't for access to the GPU? Funny thing. LR CC works flawlessly with the preferred GPU, but PS CC sucks. What to do?
I've just found that the CUDA cores on the Nvidia cards can be assigned by program specifically to one graphics card. Go to nvidia control panel and then 3D settings (Yes, 3D settings). then add photoshop and/or lightroom from the add button. the RHS window now allows you to assign the program to the correct nvidia graphics card CUDA cores. This seems to work fine for photoshop but lightroom still reports using the non chosen option. Looks like lightroom needs to be updated to pull the hardware assignment from the nvidia configuration instead of making its own choice...