So even I pass-through an AMD professional graphic card to a VM, I still can't remotely connect to the VM and use it as a virtual graphic workstation?
No, that is not what I said. There are other solutions potentially could achieve this that do not need a "capture API".
But this does not currently work with Horizon View and PCoIP since AMD GPU:s does not have a capture API. (That I know of...)
But, if I pass-through a NVIDIA professional graphic card - because NVIDIA has the "Proprietary Capture APIs", I can use the full rendering power of the discrete graphic card - from a remote Zero Client / low configuration PC / laptop
Is that correct?
Yes, with the vDGA functionality (currently in Tech Preview) you can dedicate a supported Nvidia GPU (Most of the professional cards, not the gaming GPU:s) to a VM and remote to it with PCoIP from a client that supports PCoIP (There are clients for all major platforms) and fully use the GPU rendering power.
// Linjo