Nvidia driver with dual monitors on X 4.3.0

[yussef milburn]

Prior to X 4.3.0 i was using the 'nvidia' driver for my primary agp card [geforce2] and the default 'nv' driver for my secondary pci vanta card. Along with Xinerama this was working fine for dual monitors.
However, with the upgrade to 4.3.0 I can no longer use this combo. When i start X it will lock my system up, displaying the default X backgroup [greyish] along with the 'x' mouse cursor, which i can move, but thats about all i can do. I cant kill X or reboot the system locally. I have to ssh in from another box and reboot.
I've tried using the 'nvidia' driver for both cards, but my pci card doesnt initialize properly, due to a documented bug:

nvidia1: <Vanta> irq 11 at device 9.0 on pci0
nvidia1: Unable to allocate NVIDIA register resource.
device_probe_and_attach: nvidia1 attach returned 6

However, the workaround the NVIDIA FAQ lists for this bug:

add hw.pci.allow_unsupported_io_range="1" to /boot/loader.conf

doesnt seem to work for me. If i change the vga boot device in the bios from agp to pci, the pci card will work fine using the nvidia driver, but the problem is simply reversed, and the agp card doesnt work.

It would be nice to use my 2nd monitor again. any ideas are much appreciated, thanks.

yussef