28 PowerEdge M520 Technical GuideThermal control also detects and responds to hardware configuration. Thermal managementadjusts cooling according to what the system really needs, and draws lower fan power draw andgenerates lower acoustical noise levels than those without such controls. Environmental specifications: The optimized thermal management makes the PowerEdge M520reliable under a wide range of operating environments as shown in Table 23. When operatingabove 30°C ambient, performance impacts may be seen. For more information see theDellPowerEdge M520 Systems Owner's Manual on Support.Dell.com/Manuals.The acoustical performance of the PowerEdge M520 is reflected in Table 15. The addition of somecomponents can cause an increase in fan speed and acoustical output. Contributors to acousticaloutput can include: The system thermal profile selected in BIOS (for example, Power optimized DAPC orPerformance optimized) Number of installed processors Population of modular, non-homogenous modular deployment Impedance of blanksConfiguration(23 ± 2°Cambient)CPUs Harddrives DIMMs HDDcontroller NDC PCI cards OperatingmodeLWA-UL1(bels)LpA2(dBA)Minimum 1 x 80W(4 core)1 xSATA(7.2K)4 x2GBOnboardSATA NoneAnymezzaninecardStandby3 6.7 53Idle4 7.2 56Typical 2 x 95W(8 core)2 x SAS(10K)8 x4GBPERC H310(mini) 1GbAnymezzaninecardStandby3 6.8 53Idle4 7.2 561LWA-UL is the upper limit sound power levels (LWA) calculated per section 4.4.1 of ISO 9296 (1988) and measured inaccordance to ISO 7779 (2010).2LpA is the averaged A-weighted sound pressure level of four bystanders in accordance with ISO 7779 (2010) Section8.6.2. The system is placed inside 42U rack in 25 cm height.3Standby: AC Power is connected to power supply units but the system is not turned on.4Idle: Reference ISO 7779 (2010) definition 3.1.7; system is running in its operating system but no other specific activity.