Q500 ATX case is a tower case measuring a full 24 inches high. Big case also run cooler than small case.
Less heat build up.
However, there was still room for improvements. Proper airflow though a case is the key to having a nice cool running system. Having a big case helps, but a small case with good airflow will out perform a big case with bad or no airflow. Setting up good airflow requires you to work out how air gets in and out of your case. Many people just concentrate on getting air in to a case with no thoughts as to how they will get the air out.