SEPM database migration to SQL 2008 question

Hi,,

I've migrated SEPM 12.1 database from SQL 2005 to SQL 2008 new server..it was successful..However, I need to double check what do i need to do on the SQL client installed on my SEPM server. It is still running on SQL 2005. Do I need to uninstall and install the SQL 2008 client? or no need? or can I upgrade it? or just leave it as it is.

Another question is, will my previous backup works in case I need to use it in disaster recovery. I ran that backup when my SEPM is still using SQL 2005. Now that I'm running SQL 2008..can I use thesame backup for restoration?

thanks,