Acoustics; Table 7. Acoustical Performance For Typical Configuration - Dell PowerEdge R715 Technical Manual

Dell

4.7 Acoustics

The acoustical design of the PowerEdge R715 reflects adherence to Dell's high sound quality
standards. Sound quality is different from sound power level and sound pressure level in that it
describes how humans respond to annoyances in sound, like whistles, hums, etc. One of the sound
quality metrics in the Dell specification is prominence ratio of a tone as shown in Table 7.
Table 7.
2-Socket Configuration @
CPU HDD
2 x 6400 4 x SAS
MT 10k rpm
Definitions
Idle: Reference ISO7779 (1999) definition 3.1.7; system is running in its OS but no other specific
activity.
Stressed Processor: An operating mode per ISO7779 (1999) definition 3.1.6. The software
SPECPower_ssj2008 is utilized to stress the processors. SPECPower is set to 50% loading.
LwA – UL: The upper limit sound power level (LwA) calculated per section 4.4.2 of ISO 9296 (1988)
and measured in accordance to ISO 7779 (1999).
LpA: Average bystander A-Weighted sound pressure level. The system is placed in a rack with its
bottom at 25 cm from the floor. The acoustic transducers are at the four bystander positions, ref
ISO7779 (1999) Section 8.6.2.
Prominent tone: Criteria of D.5 and D.8 of ECMA-74 9th ed. (2005) are followed to determine if
discrete tones are prominent. The system is placed in a rack with its bottom at 75 cm from the floor.
The acoustic transducer is at front bystander position, ref ISO7779 (1999) Section 8.6.2.
PowerEdge R715 Technical Guide
Acoustical Performance for Typical Configuration
°C
23 ± 2
RAID DIMM
PERC
16 x 4GB
H700
L -UL
Operating
WA
Mode
(Bels)
Idle 5.5
Stressed
5.5
(SP 50%)
L
Prominent
pA
Tones
(dBA)
42 None
42 None
25