Fan runs all the time at full speed when DX4000 is off

See the post above yours.  That’s the answer I got from a WD Staffer.  Not really acceptable but what are you going to do.  There are three things that I am disappointed about with this unit, 1 is the fan issue, the 2nd occurred when I bought it and I was told that it came with 4 x 1gb hard drives only to receive it in a 2 x 2 gb drive configuration.  I really wanted the Raid 5 functionality and speed vs. Raid 1, and the 3rd issue is that the latest version of Microsoft Security Essentials won’t run on the box.  I know that’s a Microsoft issue but since this is supposed to be a cost effective storage device for SMB’s and SOHO’s I think there should be an in box anti-virus solution.

Beyond that I have been happy with the unit.

I think an alternate workaround to the fan issue would be some kind of sleep mode where the drives spin down and the rest of the hardware goes into a low power consumption state.  I try to be as ‘green’ as possible but sometimes people put insurmountable roadblocks in your path.