Viewing page 4 of 7 pages. Previous 1 2 3 4 5 6 7 Next
The BIOS provides hardware monitoring of temperatures, fan speed and voltages,
but no user control. Fan speed control is automated, tied to a temperature sensor(s?)
somewhere within the system. Given these conditions, baseline system noise was
defined to be the MicroServer running with no hard drives. In actual use, this
server is not likely to get the extremely high, extended CPU or GPU loads used
routinely for benchmarking desktop PCs; idle or near idle conditions are likely
to predominate, which means the fans are not likely to ramp up in speed often.
The more significant variable is probably going to the noise made by the hard
drives, in idle and in seek.
As delivered with 2 GB RAM and...
- no drives (Baseline)
- 2 Seagate Barracuda 7200.12 160GB SATA drives
- 2 Western Digital Green 2 TB AV drives (5400 RPM)
- 4 Western Digital Green 2 TB AV drives (5400 RPM)
Measurement and Analysis Tools
GENERAL USE IMPRESSIONS
The sample HP MicroServer, as delivered with MS Windows Server 2008: R2 Foundation
installed, was hooked into the SPCR gigabit wired network, which has 4 unmanaged
switches. It was used for a week mainly as a file server and backup, roles the
MicroServer fulfilled smoothly without any issues. Transfer speeds varied depending
on the type of files and the other machines involved, but it was as speedy as
any other system in the network, reaching a maximum of 100~110 MB/s. We did
not see any significant benefit from the dual 7200 RPM drives compared to the
mostly 5400 RPM WD Green and Samsung Eco Green HDDs running on the network storage
boxes and PCs. The unit was placed in a closet, where a fanless single 2TB HDD
NAS box resides. This system is inaudble outside the closet; the Seagate-equipped
HP is audible, though subdued.
Other functions such as e-mail, database or intranet Web server were not explored.
We have no doubt that the MicroServer can handle all such functions with the
user number suggested by HP: 10 or fewer. Users will likely experience slowdowns
at the higher end of the recommended number.
PRELIMINARY NOISE CHECKS
1. Baseline Noise: This is defined as the lowest possible noise level
of the system. Adding any other components can only increase the noise. The
hard drives were removed, and the system booted into the BIOS menu. It was left
running for about five minutes before any measurements were taken.
23 dBA @ 1m in our anechoic chamber.
Our baseline measurement is 2 dBA higher than HP's claim of 21 dBA for the
MicroServer, which is pretty close, given that HP used the >1m ISO 7779 "By-stander"
position for the mic. The overall noise level is modest, and the noise quality
is not bad. Though it has distinct tonal aspects and is several decibels louder
than the noisiest PC in the lab (~16 dBA@1m) we could live with the noise.
2. As Delivered, with two Seagate Barracuda 7200.12 160 GB HDDs: Surprisingly,
the measured SPLwas almost identical, whether one or both drives were engaged.
The difference in perceived noise between no drives and with these drives running
was night and day, however. The acoustic signature of the sample as delivered
is best described as extremely tonal, annoying and difficult to tolerate for
any length of time in a quiet environment. Perhaps in a busy office with lots
of other machines running, its noise would fade into the background buzz, but
in our quiet lab, no way. The fault lies much more with HP's choice of hard
drives than in the MicroServer.
Still 23 dBA @ 1m but with a completely different sonic signature.
Without the Seagate drives, there was no output above 3 kHz. With them,
the upper range is riddled with highly audible tonal spikes.
3. With two WD Green 2TB HDDs: This was to confirm our perception that
the Seagate Barracudas caused much of the annoying acoustic character of the
sample system, as delivered. WD Greens are currently our favorite quiet HDDs,
widely available at low prices, and used by many SPCR enthusiasts. As expected,
with the WD Green drives, the overall acoustic character became much closer
to the baseline, even though the measured SPL was slightly higher than with
the Barracuda drives. Again, while the overall level is a bit higher than we
prefer, we can live with this noise.
With WD Greens, the same measured SPL as the Barracudas, but virtually
no increased high frequency noise. The recording shows slightly higher
broadband noise but no increased tonality over the baseline noise.
4. With four WD Green 2TB HDDs: The measured SPL barely went up, to
24 dBA, and the subjective impression was the same. The fact that the noise
level rose so little tells us that other sources of noise in the system set
the noise floor, not the very quiet WD Green drives.
|Help support this site, buy the HP MicroServer from one of our affiliate retailers!|