Just a possible hint:
Once I owned a Voodoo4 4500 Mac Version with DVI output. The idea was to test, wether the DVI output would work or not in a mediator amiga setup. For this purpose I needed to flash the rom of the card to PC version. That was no problem, the card worked fine in a PCI PC setup, but DVI didn’t in amiga setup. There was an option to flash it back to Mac version afair.
I thought it could be helpful for you to know, if you don’t already, that there is a possibly a way to do a „reverse flash“ with a Voodoo5 PC PCI version of the card.
Anything I mentioned here is referring to the PCI Voodoo card versions.