As for the Voodoo 4-2 4000 AGP 16MB Rev.A0 4100 Xion has it's Bios reads Voodoo4 4000 AGP also something weird, since the one on your site is corrupted Chosen_One, it might be an idea to ask Xion to do a Bios Dump for your collection to get that fixed, just the name is confusing maybe it's just a Voodoo4 4000 AGP 16MB after all and we always had given it the incorrect name ever since?
Even I know it does use a VSA-101 Daytona, I found this out on Xion's 3dfx Gallery page here of this particular card:
https://www.dusty-voodoo.com/3dfx-Prototype…X-16MB-Daytona/