"Theoretically, this syntax could be used to start Windows NT on any drive in the system. However, this would require that all drives are correctly identified through the standard INT 13 interface; since support for this varies from disk controller to disk controller and most system BIOS only identify a single disk controller through INT 13, in practice it is only safe to use this syntax to start Windows NT from the first two drives connected to the primary disk controller, or the first four drives in the case of a dual-channel EIDE controller."
To avoid tears put Windows
boot drive on the first SATA socket (SATA 0)
Mac