PPC Mac video card?

[Arc Riley]

This is a long shot, but no harm in trying

I was given a G3 tower to help port some free software to OSX, but
unfortunately the video card (Rage128) is far too old to run the
software.

It's a G3 PCI tower (no AGP) running OS10.4.

Does anyone happen to have a better mac PCI video card laying around?
Perhaps in a broken tower or left over from an upgrade?  Even a
nForce2, Intel i915, or low-end Radeon would be sufficient.  While it
uses a PCI video card, apparently not just any PCI video card will
work due to some board firmware requirement.  Some cards can be
re-flashed for the Mac but they've extremely specific and almost
impossible to find new anymore.