Noise pollution
The last test concerned hard drive noise levels. We took several measurements with a sound measuring device from 3 cm from the hard drive.
Of course, the Hitachi, Maxtor and Seagate with their hydro-dynamic (Fluid Dynamic Bearings) engines were in the lead. If Hitachi and Seagate had almost the same amount of noise, Maxtor is clearly ahead and offers truly silent hard drives in this area.
Western Digital with its ball bearing engine for 7,200 RPM hard drives came in last. The Western’s equipped with FDB engines are usually destined for the OEM market. Though difficult it’s also possible to find them on the retail market. Their extension for ATA with 2 MB of cache is LB, and PB with 8 MB of cache.
The next graph includes measurements during intensive use.
Without AAM (Audio Acoustic Management), in performance mode, the Maxtor hard drives were noisy even if they were almost silent in rotation only. This problem is resolved if the AAM is activated, but access time is 20 ms.
For Western, the noise level difference from rotation is reduced. However, even if the difference was small, starting from 45 dBA necessarily gives higher figures. Hitachi’s 7K250s had better results and these hard drives are the least noisy with or without AAM.
The Seagate 7200.7 in the ATA version with the non modifiable activated AAM is discreet, but provides reduced performances. The 7200.7 SATA is the noisier hard drive of this comparative test, and it is a first for Seagate. It’s a shame that the firmware provided with the disc doesn’t provide the opportunity to activate the AAM to reduce the noise level.
UpdateThe 7K250s have an ITF function (Idle Time Function), which after ten minutes of inactivity moves the reading head arm (this time laps may vary). If our test hard drives purchased in retail outlets didn’t produce any specific sound, this doesn’t seem to be the case for all 7K250s. Some users had hard drives that made noticeable noise in silent configuration in which the disc isn’t active during certain periods. This noise can last from 0.5 to 1.5 seconds.
