Changing phpMyAdmin password on XAMPP (Linux)
http://linux.justinhartman.com/Setting_up_a_LAMP_Server#Creating_users_to_use_MySQL_and_Changing_Root_Password
mysql is located in /opt/lampp/bin/mysql so instead of mysql -u root just do /opt/lampp/bin/mysql -u root
You also need to go to /opt/lampp/phpmyadmin/config.inc.php and change the password in there too.
The first part was changing your mySQL database password and the second part is changing your phpmyadmin password.












