Any 32bit operating system capable of running PHP5
PHP5, requires version >= 5.1.0 (it might work with earlier versions but this is not officially supported)
Any 32bit operating system capable of running PHP7.0(version 4.x.y only)
Enabled GD 2.x library in PHP installation. This is normally bundled with the PHP distribution. It is strongly recommended that you use the included version of GD with PHP and not try to install it separately.
For more detailed information on PHP settings in php.ini
see Verifying the PHP/GD installation