I have a multi gpu setup with 3x GTX 660 gpus, connected to a video wall of 12 monitors (each GPU connected to 4 monitors) running Linux. In order to render on all of these monitors, i tried to work around the X problem mentioned in other posts (for example https://devtalk.nvidia.com/default/topic/1028908/vulkan/vkenumeratephysicaldevices-only-lists-1-of-3-gpus-from-x-env-all-3-from-tty-/) by using direct rendering. However, this only works when rendering to 4 or less monitors. Note that it doesnt matter which 4 monitors: any 4 will work, but no more.
Is there anything i’ve missed or is there a driver limit or bug?