XF 1.5 changing domain names


I had originally installed xenforo at abc.com now I want to change it to xyz.com (on the same host / server). On the domain / host front I know that I need to change my main domain name from abc.com to xyz.com. However, what needs to change on xenforo?

Do I need to backup my database and server files and do a fresh install and restore the backup? Or can I just change the domain name in the config.php and the admincp?