Backup problems..

Hello. I needed to change my host, and i did a backup from phpmyadmin.
The backup have 21mb and I subdivided it in +- 15 parts, like i did in my forum (ipb) backup.
But i’m having a error when trying to send some parts if backup =/

This is the error: Fatal error: Maximum execution time of 300 seconds exceeded in /usr/local/cpanel/base/3rdparty/phpMyAdmin/libraries/string.lib.php on line 91

Someone can help me? What can I do now? I’m not having success to make the backup on new host 🙁

Thanks guys..