| Hello,   I have tried vga passthrough on my open 
suse11.4(xen4.0.2) today. (vga card: nvidia QuadroFX5800) After enable vga 
passthrough, the guest VM(windows2003x64) becomes very slow for any 
operation including OS startup, mouse moving. And the guest's CPU 
utilization always keeps high(40% +), it should be consumed by windows kernel 
because I didn't see any process use such cpu resource from task 
manager. But this issue is not happen on another QuadroFX1800 machine, 
does vga passthrough depends on graphic hardware? since 5800 has 4G video memory 
but 1800 only has 768M. My guest configuration as below:   name="w2k3x64_2"description="None"
 uuid="dd12d5fa-57d0-9a56-8cbb-44495f9fecd3"
 memory=4096
 maxmem=4096
 vcpus=4
 
 
 
 localtime=1
 keymap="en-us"
 builder="hvm"device_model="/usr/lib/xen/bin/qemu-dm"
 kernel="/usr/lib/xen/boot/hvmloader"
 boot="c"
 disk=[ 
'phy:/dev/lvm/win2003,hda,w',]
 vif=[ 
'mac=00:16:3e:7b:07:29,bridge=br0,model=rtl8139', 
]
 gfx_passthru=1
 pci=['03:00.0']
 stdvga=0vnc=1
 vncunused=1
 viridian=0
 usb=1
 acpi=1
 pae=1
 usbdevice='tablet' serial="pty"   Thank you, Jin |