To increase the reliability of power supply, operating ambient temperature inside the end system enclosure should be maintained between 25 to 35degC. Select power supply which has 20% more power than actual need. For example, if the system needs a 200W it is suggested to select power supply rated for 240W output power or more. Reducing operating ambient and selecting higher rated power supply will increase the reliability of the power supply in end system. User need to ensure that temperature of critical part is well within its safe operating limit under worst operating conditions.