Technical Guide

L
pA,m
: The declared mean A-weighted emission sound pressure level is at the bystander position per section 5.3 of ISO 9296
(2017) and measured using methods described in ISO 7779 (2010). The system is placed in a 24U rack enclosure, 25 cm above a
reflective floor. Data presented here may not be fully compliant with ISO 7779.
Prominent tones: Criteria of D.6 and D.11 of ECMA-74 are followed to determine if discrete tones are prominent and to report
them, if so.
Idle mode: The steady-state condition in which the server is energized but not operating any intended function.
Operating mode: The maximum of the steady state acoustical output at 50% of Processor TDP or active HDDs per C.9.3.2 in
ECMA-74 .
PowerEdge acoustical dependencies
Some product features impact acoustical server output more than others.
The following features are considered strong drivers of acoustical response, thus configurations, or operating conditions that
include these features may increase air mover speed and acoustical output of the server:
● Ambient temperature: Dell EMC evaluates the acoustical performance of servers in a 23 ±2°C environment. Ambient
temperatures more than 25°C will have higher acoustical output and may experience larger fluctuations between state
changes.
● Processor thermal design power (TDP): Higher wattage processors may require more airflow to cool under load and thus
increase the potential acoustical output of the system.
●
Storage type: As T150 fan speed is well controlled for acoustics, noise from rotational storage media (HDDs) can be
noticeable in a quiet environment. For users sensitive to acoustics, SSD or Client HDDs are recommended.
● System thermal profile selection in BIOS or iDRAC GUI:
○ Default Thermal Profile, generally provides a lower air mover speed thus lower acoustical output than those of other
thermal profiles.
○ Maximum Performance (Performance Optimized), will result in higher acoustical output.
● BOSS module: If any BOSS module is installed and “Maximum Performance (Performance Optimized)” is selected, fan speed
and acoustical noise may significantly increase at IDLE condition.
Methods to reduce acoustical output
T150 is designed for use in data centers, some users may prefer to use it in a quieter setting. The following is a list of means to
do so.
NOTE:
In most cases, the idle air mover speed of the system cannot be lowered without changing the configuration of the
system, and in some cases, even a configuration change may not reduce idle air mover speeds.
● Enable sound cap in IDRAC GUI: Sound cap, a setting in the BIOS, can be toggled on/off during boot up. When enabled,
sound cap reduces the acoustics of the system at the expense of some performance.
● Reduce ambient temperature: Lowering the ambient temperature allows the system to cool components more efficiently
than at higher ambient temperatures.
● Set target in Third-party PCIe card options: Dell EMC provides airflow customization for third-party PCIe adapters that
are installed in PowerEdge platforms. If automatic cooling response is above desired levels (LFM) based on the card
specifications, a different LFM target can be set using PCIe Airflow Settings options in iDRAC GUI.
● Replace third-party PCI cards with similar Dell supported temperature-controlled cards, if available. Dell EMC works diligently
with card vendors to validate and develop PCI cards to meet Dell EMC’s exacting standards for thermal performance.
● Replace HDDs with SDDs
Power, thermal, and acoustics
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