Microsoft Knowledge Base Article 263532 contains the following summary:
This article describes how to perform a disaster recovery restoration of the Microsoft Windows 2000 Active Directory
domain controller on a computer that has a different hardware configuration from that of the computer where you performed
the Active Directory backup.
You may have to use this procedure if no other domain controllers exist and if no computers with a hardware configuration that is similar to that of the failed domain controller are available. This article applies to computers that are running Windows 2000 Service Pack 2 (SP2) or later at the time that the backup operation was performed.
Warning The procedure that is described in this article is intended for disaster recovery of a single domain when no other domain controllers are available. This procedure is not intended as a means to move domain controllers from old hardware operating systems to new hardware operating systems in a multiple-domain environment. It is intended for use only when disaster recovery is required. After you recover the domain controller, do not keep the recovered domain controller in production. The purpose of this recovery is to restore Active Directory functionality and to bring new domain controllers online. After a new domain controller is online, demote the recovered server, remove it from the domain, and then reinstall Windows.