Well THAT you should be able to do. Set up a VNC using a display on the discrete GPU. If you find this to be difficult, there are ways to force a GPU to display something without a monitor.
Originally Posted by kobblestown
1. VNC is insufficient. I want sth with synchronized audio and USB redirection. Something along the lines of SPICE. I want to connect to the VM, not to some server inside it. Because I might need to run various OSes.
Originally Posted by schmidtbag
2. I really doubt that VNC can remote accelerated 3D graphics. I think VNC implements a X11 display entirely in software and eschews any acceleration. I'd like to be proven wrong though. In any case, it doesn't work very well for remote Windows desktops.
Actually, I'm indifferent to whether the VM gets a dedicated GPU or whether the GPU is virtualized but the host GPU is used to accelerate the guest display. If course, the former will offer better performance but the latter has better flexibility. For instance, the possibility to run several VMs with a single GPU without requiring VT-d. Sure, there will be a performance hit but I mostly need this for desktop effects, so it should be fine.
More specifically, I would like to get an Supermicro X9SCL-F main board. It has IPMI 2.0 compatible BMC module with its own graphics controller. It doesn't make use of the CPU-integrated GPU. Then pair it with a Xeon E3 CPU with an integrated GPU. Then I would like to run VMs on it that make use of the integrated GPU. I don't even know whether this is possible. Maybe when the mainboard doesn't support the integrated GPU it cannot be used at all. It should be able to render to a buffer - I don't need it to output a video signal, just to generate the images which can then be handled by the hypervisor. But I don't know if that's possible both in terms of the hardware being capable to do it and the hypervisor being able to exploit it. I haven't been able to find information on such use case that far.
Help me Obi-Wan Kenobi, you're my only hope