Home > Servers > PowerEdge Components > White Papers > Dell 15G PowerEdge Acoustical Experience and Dependencies > Tips for acoustically sensitive environments
Thermal management and associated air mover speeds (re fans, blowers, etc.) to cool components to comply with their specified limits are most responsible for sounds from computers. Amplitude of sound scales logarithmically with the speed of air movers, so a seemingly small speed adjustment can have surprisingly noticeable impacts. For example, a 10% speed change results approximately in 2 dB sound pressure level change while a 20% speed change results approximately in 5 dB sound pressure level change.
With that in mind, some common thermal drivers and tips to address them for acoustically sensitive environments are described in Table 2. Note that as ambient temperature, component power, and/or loading become sufficiently low that air movers are spinning at their minimum speed, other components may become audible (such as the hums from Hard Disk Drives and ringing from capacitors).
Driver | Description | Tip |
GPU / FPGA / Accelerator Cards |
| If deemed an acceptable compromise to accommodate the environment, uninstalling the GPU or running it at a lower loading may reduce air mover speed and acoustical amplitude. |
PCI Cards | Dell works diligently with card vendors to validate and develop PCI cards to meet Dell’s exacting standards for thermal performance. Although Dell’s products can look up and cool appropriately for various cards, some third-party cards may be unknown and thus air mover speed may be higher for thermal protection. |
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Storage Type | NVME SSD consumes more power than SAS/SATA drive technologies and therefore demands more airflow to achieve system cooling targets thus higher air mover speeds. | If deemed an acceptable compromise to accommodate the environment, replacing NVME SSD devices with SAS/SATA drives may reduce acoustical amplitude. |
Thermal Design Power (TDP)
System thermal profile selection in BIOS or iDRAC GUI | Higher wattage components under load may require more airflow and thus higher air mover speeds and louder host system.
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BOSS S2 module | If any BOSS S2 module is installed and “Maximum Performance (Performance Optimized)” is selected, air mover speed and acoustical noise may significantly increase at idle condition | |
Ambient Temperature | ISO standards, ECMA standards, and Dell specs require acoustical tests in 23±2°C ambient temperature. When ambient temperature is higher, air movers must speed up to compensate and thus generate more sound. |