Você seguiu as etapas deste artigo?
Como mover o link do banco de dados do site
ATUALIZAÇÃO: de link
If you moved the Site Database to another server, you need to run the Microsoft System Center Configuration Manager Setup Wizard on the Microsoft System Center Configuration Manager 2007 Server to modify the SQL Server configuration to specify the new SQL Server name.
Ensure the primary site server computer account has administrative privileges over the new site database server computer.
Close any open Configuration Manager console connections to the site server.
On the primary site server computer, use the hierarchy maintenance tool (Preinst.exe) to stop all site services with the following command: Preinst /stopsite.
On the primary site server computer, click Start, click All Programs, click Microsoft System Center, click Configuration Manager 2007, and click ConfigMgr Setup, or navigate to the .\bin\i386 directory of the Configuration Manager 2007 installation media and double-click Setup.exe.
Click Next on the Configuration Manager Setup Wizard Welcome page.
Click Perform site maintenance or reset this site on the Configuration Manager Setup Wizard Setup Options page.
Select Modify SQL Server configuration on the Configuration Manager Setup Wizard Site Maintenance page.
Enter the appropriate SQL Server name and instance (if applicable) for the new site database server as well as the site database name on the Configuration Manager Setup Wizard SQL Server Configuration page.
Configuration Manager Setup performs the SQL Server configuration process.
Restart the primary site server computer, and verify the site is functioning normally.
Note: If you also need to move the Software Update Services Database (SUSDB) you will need to stop IIS Admin Service, and Update Services Service and follow Steps 1 and 2 above to detach, then move the SUSDB.MDF and SUSDB.LDF files, then attach the SUSDB.MDF, in the new drive location or on the new SQL Server 2005.