Well, if it comes to that, maybe we can go that route, though I really would prefer you review the DH WIki article on Migrating MySQL databases , and give it a try first.
It is really described about as well there as I am likely to be able to do it, and between that and a little google time, I suspect you'll be up and running in no time.
Pay particular attention to the shell/command line sections of the article, as you have already determined that PhpMyAdmin can't handle a file that size.
Make sure also that your user is set up to be a "shell" user, and that you can access the shell via an ssh client program before proceeding. If you need help with that, start with the DH Wiki article on the shell, and follow the "see also" links you will find there for ssh, shell commands, and enabling shell access.
If after you have read the indicated material, and given it a try, if you post back with a specific question I'm happy to try to help you further.