backed up computer, got new mother board

Hi, I have a MacBook Pro and I backed up my system, and I had a brand new mother board put in, and I need to know what to do now. The back up says that that it was created on a different computer, and if I reuse this back up, It can no longer be used on the original computer, and I am sure it is because I have a new mother board, so do I just reuse backup, or create a new one? My gut says reuse it.

Thanks

G'day and welcome to the forums.

Helps if you tell us what operating system you are running. If OS X.6 or earlier boot from the install disc and when finished use Migration Assistant to back everything up from the external drive. You could always use Disk Utility's Restore if a later system.