PHP try/catch and fatal error when mysql is down!

try{
   $db = new PDO('mysql:host='.$host.';port='.$port.';dbname='.$db, $user, $pass, $options);
}

$db = new PDO('mysql:host='.$host.';port='.$port.';dbname='.$db, $user, $pass, $options) or die("Cannot Create PDO!");

$db = new PDO('mysql:host='.$host.';port='.$port.';dbname='.$db, $user, $pass, $options) or ($GLOBALS['errors'][] = "Cannot Create PDO!");