We have installed PHPMyAdmin on a windows machine running IIS 7.0.
We are able to connect to MySQL using command-line, But we are not able to connect using PHPMyAdmin.
You need to do two additional things after following the link that you have mentioned in your post:
One have to map the changed login cridentials in phpmyadmin's config.inc.php
and second, you need to restart your web and mysql servers..
php version is not the issue here..you need to go to phpmyadmin installation directory and find file config.inc.php
and in that file put your current mysql password at line
$cfg['Servers'][$i]['user'] = 'root'; //mysql username here
$cfg['Servers'][$i]['password'] = 'password'; //mysql password here