These “Green” WD RE4-GP drives implement an Idle3 mode which was designed to reduce power consumption, in part by positioning the heads in a park position (unloading the heads) and turning off unnecessary electronics, resulting in substantial power savings. The only problem was that as soon as Idle3 mode kicked in (after 12.8 seconds of inactivity) the ReadyNAS Pro woke it straight back up again with background system activity. This meant that the drive heads were being mechanically parked and unparked every 13 seconds … About 6,500 times a day!

Through a little Googling, with some trial and error I found a long lost Western Digital utility (WDIDLE3.EXE) which allowed you to adjust the amount of time before the drive went to sleep.

Many ReadyNAS users opted to disable the “Idle3″ feature, but this really defeated the purpose of paying the extra money for these Green drives. Instead, after setting my idle timeout to 254 milliseconds, everything went back to normal … The drives went into idle mode properly without be woken by the ReadyNAS, my S.M.A.R.T LCC attribute remained at sensible levels and my power bills stayed down.

Since then ReadyNAS’s RAIDiator operating system has been upgraded to 4.2.8 (x86) and now contains an O/S fix to prevent the WD RE4-GP from powering up prematurely. Problem now solved!

Regardless of this ReadyNAS Pro specific fix, I’ve had people on a weekly basis email me about getting a copy of the WDIDLE3 executable! Instead of me mailing it out each time, I’ve decided to bundle it up into a ISO CD that you can just boot off directly which you can download from wdidle3.iso.zip.

If you were too afraid to upgrade to RAIDiator 4.2.8 or you just want to revert their previous Idle3 firmare changes can follow these simple instructions.

WARNING! The following instructions and ISO worked for my own drives, but may not work for yours so use at your own risk. My own hard drive model numbers are “WDC WD2002FYPS-01U1B0″ and their firmware versions are “04.05G04″.

1. Download the WDIDLE3 ISO from wdidle3.iso.zip (294.2 kB).
2. Burn the WDIDLE3 ISO to CD.
3. Attach your WD RE4-GP to a PC and boot from the WDIDLE3 ISO CD.
4. At the DOS prompt type “WDIDLE3.EXE /S254” to increase your timeout or “WDIDLE3.EXE /S128” to restore it back to normal.
5. Power down your PC and remove your WD RE4-GP.
6. Insert WD RE4-GP back into your ReadyNAS and check your S.M.A.R.T LCC count isn’t incrementing wildly!

You can read more about this compatibility issue here at the ReadyNAS Hardware Compatibility page.