Last week, the fine Redditors of /r/DataHoarder got upset with Western Digital again—this time, for misrepresenting the rotational speed of their WD Red Network Attached Storage hard drives. (Although the linked post brings things to a head, members of the German-language forum hardwareluxx.de began investigating the issue more than year ago.)
We found this controversy reminiscent of earlier complaints that Western Digital was not properly disclosing use of Shingled Magnetic Recording technology in their NAS drives. But the new complaint is that Western Digital calls 7200RPM drives “5400 RPM Class”—and the drives’ own firmware report 5400 RPM via the SMART interface.
Recently, redditor /u/Amaroko set out to prove or disprove earlier netizens’ findings. For each of several drive models, Amoroko placed a sample of that drive on an empty cardboard box, with a Blue Yeti mic held directly above it, then powered the drive on. Spectral analysis of the recorded audio using Adobe Audition showed a baseline frequency of 120Hz for two models of WD 8TB “5400 RPM class” drive.
120 cycles/sec multiplied to 60 secs/min comes to 7,200 cycles/min. So in other words, these “5400 RPM class” drives really were spinning at 7,200rpm
At first blush, this might seem like a non-issue—who wouldn’t prefer a drive with a faster spindle speed? Unfortunately, faster spindles don’t just mean potentially lower seek latency—they also come with a sharp increase in both noise generation and power consumption.
That increase in noise and power is what got many users on the trail of Western Digital’s fake 5,400rpm spindle speed in the first place—those users purchased drives which they expected to roll low and slow, but they got more noise, heat, and power consumption than they expected.
Western Digital’s response
For select products, Western Digital has published RPM speed within a “class” or “performance class” for numerous years rather than publishing specific spindle speeds. We also fine-tune select hard drive platforms and the related HDD characteristics to create several different variations of such platforms to meet different market or application needs. By doing so, we are able to leverage our economies of scale and pass along those savings to our customers. As with every Western Digital product, our product details, which include power, acoustics and performance (data transfer rate), are tested to meet the specifications provided on the product’s data sheet and marketing collateral.