Duel Monitor with Agp and PCI Graphics Cards

I"m trying to do a duel Monitor setup and still be able to play halo. I have a AGP Geforce2 MX400 and a Old PCI Tseng Labs ET6000, and I would like to have duel monitors and still be able to play games on the Geforce2 Card.

In the Bios if i enable PCI as Default Graphics Boot Device, Windows AGP Main Desktop: both work, Halo doesn't Run.

In the Bios if i enable AGP as Default Graphics Boot Device, Windows Can't Extend Desktop to PCI: second pci graphics card doesn't work, Only Detected and installed.

Also PCI Card is in 3rd PCI Slot down.

Motherboard: GA-6vx7-4x
Bios Up to date

 

Also Forgot it has Windows XP Home
And have searched for information but found nothing useful.