Comment # 2 on bug 58660 from Alex Deucher

Please attach the dmesg output when booting with both video bioses.  Also,
please attach both video bioses.  To dump the video bios:
(as root)
(use lspci to get the bus id)
cd /sys/bus/pci/devices/<pci bus id>
echo 1 > rom
cat rom > /tmp/vbios.rom
echo 0 > rom