Chapter 1: Introduction I/O Shield The SC822 is a 2U rackmount chassis. Its I/O shield provides seven moth- erboard low profile expansion slots, two COM ports, two USB ports, PS/2 mouse and keyboard ports, sound ports and one Ethernet port. See Figure 1-1 for locations. Figure 1-1. I/O Backpanel Cooling System The SC822 chassis has an innovative cooling design that includes four 8- cm redundant system cooling (intake) fans. The fans plug into chassis fan connectors that are located behind the HDD drive bays. These fans run continuously at full rpm. If they break down, the ambient air temperature inside the chassis will rise and activate an overheat LED. 1-3