E:Setup /QUIET /ACTION=REBUILDDATABASE /INSTANCENAME=InstanceName /SQLSYSADMINACCOUNTS=administrator /SQLCOLLATION=French_CI_AI
E:SQLsetup.exe will need to be replaced with the locations of the SQL Server 2008 R2 setup.exe path.
MSSQLSERVER represents the default instance, if you have a named instance this must be changed to hold the instance name.
French_CI_AI: is the new collation name.
administrator need to be replaced with the local administrator of the server or PC you are installing the SQL on.
Paste above command into CMD and wait for 3-4 minutes, you will have your SQL Collation changed.