ISA cards could be used with a suitable driver running on the bridgeboard but there is no such driver. I wanted to try writing something but I never got my hands on a working bridgeboard. With that kind of setup the x86 CPU could just use the card's VESA BIOS to set the screen mode and could even act as blitter or whatever. The only problem is that the Amiga has to pass data through a 32KB window IIRC.
BTW, nVidia GeForce 8 cards are available on both PCI and AGP, and I recall a 9400 PCI being announced so that may exist also.
