Update on VGA Passthrough

[Liwei <xieliwei@gmail.com>]

(Cross posting to devel and users just this once. Will continue to
respond to the list that picks up on this.)
Hello list,
    I've did more trials today trying to get hardware graphics
acceleration to work in Windows 7.
    First thing I tried is direct PCI passthrough of the graphics card
with gfx_passthrough = 0 after reading that there was success using
this method instead of VGA passthrough (
http://xen.1045712.n5.nabble.com/VGA-passthrough-success-with-doubts-td3385438.html
). Managed to install windows through the VNC console and the card was
listed in device manager. The drivers installed successfully but after
a reboot, device manager says the card reported problems and refused
to start up (Code 43). So much for that method (maybe ATI cards are
more passthrough friendly?).
    With windows already installed, I just changed gfx_passthrough =
1, thus bypassing the installation problems.
    First up, as usual, having a large amount of memory seems to crash
windows with gfx_passthrough = 1. I didn't test exactly what happens
depending on the amount of memory allocated but instead set it to
2048.
    Windows managed to boot with that setting with a very crappy 256
(?) colour 800x600 (?) display on my monitor. Device manager says the
same thing (that the card reported problems). At least something shows
up.
    I repeated the same steps for the secondary graphics card (for
both PCI and VGA passthrough) with the same results.
    At this point, I'm starting to wonder if my hardware is capable of
doing hardware graphics acceleration on HVM windows. Maybe I need to
change my graphics card (Palit Nvidia GTX460) or my mobo (EVGA
Classified 200)?
    Pointers anyone?

    (Also, I take it that the Boch BIOS does not initialise USB
devices on bootup, since mouse and keyboard do not work until booting
into an operating system?)