Reference Guide

42 PowerEdge R720 and R720xd Technical Guide
> Hot spare feature of power supply unit: In the system default setting, the Hot Spare
Feature is disabled; acoustical output from the power supplies is lowest in this setting.
Table 21 and Table 22 detail the acoustical performance for the R720 and R720xd.
Table 21. R720 acoustical performance (2.5-inch chassis)
Configuration
(23 ± 2°C
ambient)
CPUs
Hard drives
Power
supply
unit
Memory
PCI
card/HDD
controller
Operating
mode
LWA-
UL1
(bels)
LpA2
(dBA)
Prominent
tones3
Minimum
1
1 x 250GB
SATA (7.2k)
1 x
495W
1 x
8GB
1 x PERC
H310
Idle
4.0
20
None
Stressed
4
4.1
20
None
Typical
2
6 x 300GB
SAS (10K)
2 x
750W
8 x
8GB
1 x PERC
H710,
1 x GbE
NIC
Idle
4.4
25
None
Stressed
4
4.5
26
None
Table 22. R720xd acoustical performance (2.5-inch chassis)
Configuration
(23 ± 2°C
ambient)
CPUs
Hard drives
Power
supply
unit
Memory
PCI
card/HDD
controller
Operating
mode
L
WA
-UL
1
(bels)
L
pA
2
(dBA)
Prominent
tones
3
Minimum
1
1 x 250GB
SATA (7.2k)
1 x
495W
1 x
8GB
1 x PERC
H310
Idle
4
4.7
28
None
Stressed
5
4.8
28
None
Typical
2
14 x 300GB
SAS (10K)
2 x
750W
8 x
8GB
1 x PERC
H710,
1 x GbE
NIC
Idle
4
4.8
28
None
Stressed
5
5.0
30
None
1
LwA – UL is the upper limit sound power levels (LwA) calculated per section 4.4.1 of ISO 9296 (1988) and measured in
accordance to ISO 7779 (2010).
2
LpA is the average A-weighted sound pressure level from the four bystander positions calculated per section 4.3 of
ISO9296 (1988) and measured in accordance with ISO 7779 (2010). The system is placed in a half rack enclosure (base of
system is 25 cm above reflective floor).
3
Prominent tone: Criteria of D.6 and D.11 of ECMA-74 11th ed. (2010) are followed to determine if discrete tones are
prominent. The system is placed in a half rack enclosure (base of system is 75 cm above reflective floor) and acoustic
transducer is at front bystander position, ref ISO 7779 (2010 Section 8.6.2).
4
Idle: Reference ISO 7779 (2010) definition 3.1.7; system is running in its OS but no other specific activity.
5
Stressed processor: An operating mode per ISO 7779 (2010) definition 3.1.6. The software SPECPower at 50% loading is
activated to stress the processors.
For more information on Dell’s acoustical design, see the Dell Enterprise Acoustics white paper.