would need an ARC firmware and HAL port to the older chipsets (should be possible, I know Bandit has a PCI config bit to switch endianness over the PCI bus, but I'm not sure if that does the same as what Grackle's PICR1.LE_MODE does, or if additional workarounds would be needed in drivers there)It only supports Gosammer boards currently, not sure what it would take to get it to work on anything older.
...also, drivers. Grand Central has no IDE; so a SCSI driver would be needed for ARC and NT there.