These get mentioned occasionally and are somewhat cheap.

From what I gathered they won't work on motherboards without AGP slot, although they're PCI...
But it's similar with PCI ATI Rage XL cards from aliexpress, they won't work on older motherboards, but coincidentally work on ones with AGP slot. Although it doesn't have anything to do with AGP per se, it's more to PCI standard used in pre AGP motherboards where they don't have 3.3V on PCI connector, so if you add voltage regulator and pass it to appropriate point on the card it suddenly works fine.

Has someone tried this with one of these FX cards? Only mention I found about this is one twitter post

https://twitter.com/richardg867/status/1506842032681148418/

Additionally, I think these cards would need a bit more power to work than small AMS1117 3.3V voltage regulator we use for Rage cards can provide. Any ideas/clues?