WD20EARS spinning at 7200rpm ?!


#1

Hello,

I’ve bought 2 WD20EARS within a couple of weeks and it seems i’ve got 2 different versions :

  • One MVWB0 which is clearly what I expected : a silent 2TB drive

  • One 00S8B1 which is clear what I didn’t want to buy : this drive is spinning at 7200rpm, and I wanted a silent drive to build a HTPC (no need to get top performances).

How is it possible to get 2 such different drives, under the same model number ? And could it be at least possible to spin down the 00S8B1 to 5400rpm as I expected ?


#2

How are you measuring the speed? AIUI, the WD20EARS spins at 5900 RPM.

Can you upload some HD Tune read benchmarks to a file sharing service?

See these threads:

http://community.wdc.com/t5/Desktop/WD6402AAEX-new-drive-slower-than-older-drive/m-p/39315#M2116
http://community.wdc.com/t5/Desktop/Check-hard-disk-motor-speed/m-p/39279#M2114
http://community.wdc.com/t5/Desktop/WYH-TWO-DIFFERENCE/m-p/42685#M2236

BTW, a drive’s heads fly on an air bearing generated by the spinning platters. If the rotation speed were to vary, then so would the flying height, leading to variations in read/write amplitude. Therefore the heads are aerodynamically tuned to a particular speed, and that speed is tightly controlled. I expect that Thermal Flying Height Control (TFC) could compensate for minor changes, but it wouldn’t make sense to use it for wide speed variations.

That said, I am aware that WDC uses “IntelliPower”. Unfortunately WD’s public information on the technology is no better than marketing-speak:

http://www.wdc.com/en/products/greenpower/technology.asp

“For each drive model, WD may use a different, invariable RPM.”


#3

Hello,

Well in fact I’m not “measuring” the RPM but hearing and the drive is clearly rotating faster than 5400 or even 5900 : it’s vibrating a lot and feeling like a 7200RPM HDD when you put the hand on. I know it’s not a real measure but the difference in noise and vibrations is huge between a 5400 and 7200. I’ve never tested a 5900RPM drive but we can think the difference with a 5400 drive is very small. So that’s why I’ve supposed it spins at 7200 :slight_smile:

Anyway, I’m very disapointed with this drive and if I could I would send it back where I ordered it (I had no choice but to put my backup on it because my backup disk is dying).

And thanks for the link on IntelliPower, it confirms my doubts : WD is hiding behind this to sell different models under the same name. Too bad I didn’t know it before my buying T_T


#4

Sounds like you have a defective drive, not a 7200 rpm one.