Today I received my Kill-A-Watt meter that was posted in the Good Deals forum ($18 delivered!) and of course the first thing I tested was the uNRAID box. 

 

Suprising results (at least to me).  Sitting idle with drives powered down the box pulls 68-69 watts.  All drives spun up it pulls 100-101 watts.  A LOT less than I figured it would have.  That certainly makes me less worried about leaving it on when not immediately using it.

 

 

What is your system setup? That power draw seems high to me, but then again I built with power management in mind.

Indeed - mine is only just above half those figures, but it will depend a lot on the hardware...  The motherboard, CPU and power supply efficiency have the biggest impact when idle.  Big power supplies often struggle to be efficient at light loadings.  The choice and quantity of drives of course are the biggest influence when spinning up.

How many drives are in your system.

 

It would be interesting to see Watts/Drive or Watts/Tb.

Mine are high?  Really!  Here are the specs:

 

Intel Q6600 Quad core CPU - I have a bunch of these sitting around from server refreshes we did so I used one

Asus P5BV-C - Same.  Was in a database server we refreshed

4 GIG DDR2 PC800 RAM

Intel Pro NIC 10/100/1000

2 x Hitachi 2TB drives (HDS5C302) I think this is the model #

2 x Seagate 2TB drives (ST32000542AS)

1 x Samsung 1TB drive (HD204UI)

1 x Seagate (ST3500320AS) Cache drive

 

Corsair 450W PS.  One of the recommended ones

 

I'm assuming it's the CPU that's pulling the most power when the drives are not spinning.

Actually it should be easy to see how much power each drive pulls by just having each one spin up.  I'll do that and post results.  I'm interested now too about that.

As for reducing power consumption ...

 

That Quad core is way overkill unless you are doing transcoding and maybe a few other things not purely "unraid".  You could consider shutting clocks down via the bios if available, and even underclocking-undervolting the processor.  That might even get you to the point that you could remove the fan on the CPU with enough case airflow, or at the least slow it way down.

 

Also shut down all other onboard features that aren't needed like the sound processor, ports, etc.  Probably not much to be gained by shutting down things like serial ports but every little bit helps.

 

Also if you aren't running anything that is really RAM intensive you could consider slowing that down as well coupled with an undervolt.  Again power and heat savings there. 

 

I've done both the CPU and memory UC/UV on my AMD 7750 w/DDR2800 and it helped.  But what I have no done is profiled just how low I can go especially on the voltage.  For that I'll need to run a CPU stress test (so need to run a LiveCD) and then a memtest to see just how low I can go before I get errors.  Given what I do with my unraid at least I know that I can pretty much slow down the CPU and Memory as slow as I want without performance loses, but I need to be sure not to slow down the bus that the SATA ports are on, nor the PCI-E bus

replacing the hardware with low power hardware will probably have a long payback period if you started with free stuff.

Yeah, the Q6600 is a power-hog when compared to i3 or i5 cpus. 

 

I had an original stepping Q6600 cpu and it was a power hog by comparison.

Does your BIOS let you disable cores?

 

Any single/dual core Wolfdale processors in that parts bin?

 

Actually I did find an E3400 celeron dual core in one of the old NAS boxes.  I'm going to swap it out and see how much lower it will take me.  I can also remove one of the ram chips as 2GB should be plenty.

 

Now it's somewhat of a mission

 

Thanks for the input all.

low noise / low power really is quite addictive   Welcome to the club.  And yes that celery will draw WAY less power.  Id be intersted to see what pulling the ram does, though I don't expect it to be that much.  But who knows.

Pulled RAM seems to be negligible but possibly 3W.

Celly drops it freaking 30W at idle!  Wow.

 

Now we're talking. 

 

30W * 24 = .72 kWh per day.  That's pennies but it ads up to about $4.00 a month.  Not worth going out and buying a new CPU (as mentioned) but since it was laying around, I'll take it!

[nodding], and now you can start playing with underclock/undervolt of the celery ... and if you use the HSF from the q6600 you might even get away without a fan (or have it running REALLY slow) and maybe even remove a case fan that isn't cooling the HD's directly.  Could save you another 10-15 watts

Pulled RAM seems to be negligible but possibly 3W.

Celly drops it freaking 30W at idle!  Wow.

 

Now we're talking. 

 

30W * 24 = .72 kWh per day.  That's pennies but it ads up to about $4.00 a month.  Not worth going out and buying a new CPU (as mentioned) but since it was laying around, I'll take it!

$4 per month * 12 = $48.  Enough to go out to a decent dinner, or to buy a few movies, or a bunch of mp3's.  I'd take it too.

 

Joe L.