xen winxp config, radeo 6770 passthrough

peter:~/xen # cat /etc/xen/vm/windowsxp2

name="windowsxp2"
description="None"
uuid="292b0651-9913-2459-5cfa-fb828f9c4314"
memory=4096
maxmem=4096
vcpus=4
# I don't know what's proper... to set 5-8, or 1,3, etc. to get non-shared cores
cpus="1,3,5,7"

on_poweroff="destroy"
on_reboot="restart"
on_crash="destroy"
localtime=1
keymap="en-us"

builder="hvm"
device_model="/usr/lib/xen/bin/qemu-dm"
#kernel="/usr/lib/xen/boot/hvmloader"

# I added this override long ago, and don't know if it is needed or has any effect
kernel_override="/usr/lib/xen/boot/hvmloader"

boot="c"
# this is an LVM disk
disk=[ 'phy:/dev/data/winxp1_disk1,hda,w', ]
vif=[ 'mac=00:16:3e:4e:c5:0c,bridge=br0,model=rtl8139', ]
sdl=0

# This next comment is old. It was when something weird happened, and the VNC client would work but the color was messed, and Device Manager said the primary card was the radeon, but obviously it wasn't.
# OLD COMMENT: setting this to 1 makes the radeon the first card, but changing the resolution and color won't work
stdvga=1
vnc=1
vncunused=1

# My sound doesn't work properly... haven't figured it out yet.
#audio=1
#soundhw="sb16"
#soundhw='sb16,es1370'
#soundhw='es1370'
#soundhw="all"
#soundhw="ac97"
#soundhw="petersoundthing"

audio=0

viridian=1
usb=1
acpi=1
apic=0
pae=1

usbdevice='tablet'

serial="pty"

# According to documentation, =1 means remove the emulated video card, and make the passthrough primary. However, it works with =0 and does not work with =1. With =1, it will show a Cirrus Logic as the first card, and a non-working radeon as the second. With =0, it uses the radeon first, and device manager has an "unknown device" which I assume is the Cirrus Logic card.
gfx_passthru=0

# devices to pass through: vga, vga audio, usb2, usb2, usb3
pci = [ '04:00.0' , '04:00.1' , '00:12.0' , '00:12.2' , '02:00.0' ]
#pci = [ '04:00.0' , '04:00.1' , '00:12.2' , '02:00.0' ]
#pci = [ '04:00.0' , '04:00.1' ]
#pci = [ '01:00.0' , '01:00.1' ]

# No idea what these are or where I got them from... but I didn't test them successfully without
xen_platform_pci=1
pci_msitranslate=1