I have managed to do PCI-e VGA passthrough with the open source Xen but the work is still in progress because although Windows XP guest can see the REAL PCI-e x16 graphics card instead of an emulated graphics driver, it cannot be initialized yet.
Thanks to Intel Engineer Han Weidong, Pasi Kärkkäinen, Boris Derzhavets, Marc, Caz Yokoyama, and others who have helped me and shared their knowledge with me along the way.
Intel Desktop Board DQ45CB with BIOS upgraded to 0093
Onboard Intel GMA 4500 Graphics (IGD)
nVidia Geforce 8400 GS PCI Express x16 Graphics Card
Fedora 11 Linux 64-bit Xen paravirt operations Domain 0 Host Operating System
Xen 3.5 Unstable/Development Type 1 Hypervisor
Jeremy Fitzhardinge's Xen paravirt-ops domain 0 Kernel 2.6.31-rc6
Primary Video Adapter: IGD
Intel Virtualization Technology (VT): Enabled
Intel Virtualization Technology for Directed I/O (VT-d): Enabled
Please see screenshots below:
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