TechPowerUp reviews Shuttle DS437T

"Although it is passively cooled, both CPU and IGP temperatures stayed within safe parameters during our tough testing procedures (59°C at load). This clearly shows how effective the DS437T's cooling system is, although it doesn't employ any moving parts. The lack of cooling fan(s) not only eliminates noise, but increases reliability as even the best fan can fail if it is operating around the clock."

Source: TechPowerUp