I'm considering a Western Digital Green drive for use in a Digital Video Recorder (DVR). This equipment does no power management itself, and won't set the drive to spin down.
I've experimented with a standard Seagate drive: by "hot plugging" the running drive into a PC, I can set the spindown setting, and then "hot plug" the unit back to the DVR. When the video recorder is in standby the drive spins down until the next scheduled recording . But the moment power is cycled, the setting is lost.
I understand that most SATA drives forget the spindown setting. However I understand the WDC Green might be different, and wonder if anyone can confirm. Will it spin down in my DVR?
Note 1: Specifically I power the drive from the DVR at all times, then hot-remove the SATA cable, hot plug into a PC running Linux, issue "hdparm -S1 /dev/sda", then hotplug back to the DVR. This fools the drive into thinking the S1 command came from the Digital Video Recorder.
Note 2: This is a Dish Network DTV Pal DVR (formerly the TR-50), and over-the-air, no-internet or monthly TiVo fee required, hard drive based video recorder which works like an extended version of a DTV converter box. It draws 22 Watts 24/7 with the stock drive, a 7200 RPM Seagate.
It does that by itself, and you don't need to set spindown mode. Spindown will spindown the drive to 0 rpm, the Green drive won't do that afaik, but will reduce the rpm to lower the idle power consumption, which is good.
I'm sure that part is not true: the WD drive has tricky marketing wording. It has an "invariant spin speed", meaning fixed.
Sorry sub mesa: just like the Tom's hardware editor you've been taken in by the marketing fluff.
If you have such a drive though, you could answer the original question with an experiment.
The WD Green is ~5400rpm yes, not 5400rpm - 7200rpm like the marketing suggest, but that wasn't what i meant. The issue is that when the drive idles, it goes even lower power idle state; though not completely spun down like with a spindown command where it goes to 0rpm; any access would need 8 seconds or so to regain its spindle speed. The WD Green appears to use some built-in mechanism to reduce idle load even more; which can be measured with voltage meter as it uses more power directly after completing an I/O request than say 10 minutes later.
What the exact story is here i don't know, but it doesn't matter really the benefit is lower power consumption especially in idle mode which is most important. The drive will be significantly less hot and won't need active cooling.
According to WD, the Green drives park the drive heads which lifts them slightly off the surface of the disk. This is done during inactivity to reduce aerodynamic drag.
But in that mode the Green drive is still using more than a comparable non-green notebook drive. I'm talking about a digital video recorder that might record 1 hour of TV every few days. It can spin to 0 rpm, especially since this involves no drive head wear.
The way to answer the question of the spindown is:
1) Set the drive to spin to 0 rpm after X seconds, and verify this works.
2) Unplug the drive. Plug it back into power only (no SATA). Does it still spin to 0 rpm after X seconds?
Has anyone done this who is willing to share data?
Tom's has already measured idle power consumption (with an amp meter, not a volt meter, of course). The drive offers pretty good results when actually idle.