For this reason it is recommended that CUDA is run on a GPU that is NOT attached to a display and does not have the Windows desktop extended onto it. In this case, the system must contain at least one NVIDIA GPU that serves as the primary graphics adapter.
does this mean the primary graphics card must be NVIDIA and cuda support?
i tried an embeded intel graphics card, it didn’t work
It definitely means that the card being used to run your display needs to be an Nvidia card. Whether the card needs to be able to support CUDA is up for interpretation, but I don’t think that CUDA support is a requirement (this is a guess).