Intelligently-engineered airflow mechanics

Intelligently-engineered airflow mechanicsLearn more about it.
The G/G2/G4/G5 Chassis
The current G series chassis feature more air intake points designed to keep the mainboard cool and stable. The chassis and underside of this Shuttle XPCs feature strategically positioned intake points that channel cool air across critical components. Size and position of these intake points are engineered to minimize noise.
The P Chassis
The Shuttle XPC P-series introduces a revolutionary new approach to airflow design. Separating the machine into 3 airflow zones: CPU, HDD and Case (including power supply, mainboard and graphics card). The airflow in the P-chassis shows several different intake points designed to keep cool air continually flowing over critical components as opposed to recalculating warm stale air. Finally, the underside of the P-chassis has more air intake points designed to keep the mainboard cool and stable.
2008

Source: http://eu.shuttle.com/en/DesktopDefault.aspx/tabid-40/857_read-12931/