How to: Change the Name of a Registered Server or Registered Server Group (SQL Server Management Studio)
SQL Server 2005
Registered Servers retains the name of the server or server group that was provided at the time of registration. The name can be changed at any time. Changing the name of a server in Registered Servers only changes how the name is displayed. To connect to a different server, you must edit the connection properties of the registered server.