CurtPalme.com Home Theater Forum

Tom.W · Joined: 09 Mar 2006 Posts: 6635

ecrabb · Posted: Tue Jul 02, 2013 3:53 pm Post subject:

Tom.W · Joined: 09 Mar 2006 Posts: 6635

The trouble with excessive parking...

http://www.storagereview.com/how_to_stop_excessive_load_cycles_on_the_western_digital_2tb_caviar_green_wd20ears_with_wdidle3

CIR Engineering · Posted: Tue Jul 02, 2013 9:15 pm Post subject:

Parking and spinning down are different things. The OS controls spin down time, but the HD firmware controls the parking time for the heads. WD Green drives are programmed to park the heads after just 8 seconds of inactivity. With Windows this is not usually much of an issue, but with many Linux based distributions the HD is written to ever 10 seconds. The result is that the Green drive parks its heads over and over every 8 seconds. According to WD, the life expectancy for parking cycles on a Green drive is 300,000 cycles. At the default rate it is possible to burn through your Green drives in less than a year!

For this reason, if you want to use WD Green drives with a Linux distribution you should either set parking to a higher value or disable it completely. I choose to disable it because I have my HD's spin down after 15 minutes anyway and the heads will park when spun down. Right now according to SMART my first hard drive has only parked 1,177 since I built that big server about eight months ago. The drive reports 6103 hours of operation.

craigr

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

stefuel · Posted: Wed Jul 03, 2013 9:51 am Post subject:

The whole idea behind the clamp-on was to give me a INDICATION of which of the three was using the most power. I still stand behind my choice to use the Precision 390. However, in the interest of putting this discussion to rest, my friend has a "kill-a-watt" meter that plugs into the wall and you plug a "device" into it. Will that satisfy all interested parties?

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

The clamp meter gives a misleading representation for the very reasons ive repeated over and over that for whatever reason you clearly do not understand. The fact you dont understand it is nothing at all against you and absolutely no disrespect is intended, majority of people do not understand it, but you would be amazed at the differences in readings you can and will get using your method Vs the correct method.

As for the other meter, id need to know brand and model number before i would trust it, most ( if not all ) plug in domestic and cheap comercial watt-hour meters are nothing but a joke cause they calculate apparent power and not true power.

This isnt about which machine will use more or less, its about correct measurements that you can actually USE to determine what components offer the best efficiency and performance. Incorrect measurements are a waste of time and tell you very little ( if not totally misleading ) information.

stefuel · Posted: Wed Jul 03, 2013 11:18 pm Post subject:

Reliance Controls THP103
Not a precision tool but I'm not trying to generate a certified elecrtric bill but it should give me a indication of which one best suits my power concerns. Then if the readings from that, multiplied by my cost per kw hr. come out even close to what I posted previously, you will feel my hands reaching through the screen to throttle you Laughing

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

Haha!!

You will need to take an average reading over 24-48 hours, and if your readings come out as high as your gestimates, i think you should throttle yourself and get another calculator Laughing

stefuel · Posted: Thu Jul 04, 2013 12:18 am Post subject:

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

About $5 - $10 a month....

ecrabb · Posted: Thu Jul 04, 2013 3:29 am Post subject:

Most newer desktops are in the 50w ballpark at idle, so probably only $7/mo. or $85/year at $.185/kwh. Throw in a high performance video card and a couple of extra 7200 RPM sata drive and you'll double that. That's at idle. If you're ripping Blu-rays or playing games, consumption shoots up.

The older Xeon server with 10000 RPM SCSI drives is probably triple that, or around 150w, so $20/mo or $250/year. Ballpark.

For comparison, a Mac mini uses low-power notebook CPU and drives, so runs only 5w or so at idle. You'd save about $75/year running a Mac mini or notebook over a desktop if you needed a 24/7 machine.

Power comsumption is another reason appliances are getting more popular.

SC

the big E · Joined: 20 Apr 2013 Posts: 1928 Location: speedwell Tn.

ecrabb · Posted: Thu Jul 04, 2013 4:26 am Post subject:

the big E · Joined: 20 Apr 2013 Posts: 1928 Location: speedwell Tn.

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

stefuel · Posted: Thu Jul 04, 2013 12:03 pm Post subject:

OK. The results using a digital "watt meter". Not to far off considering I used a example voltage and a analog meter.

This is for the Dell Precision 390 using a 80 GB drive for the OS and applications and 3 WD 2 TB drives for storage.

5 minutes after boot 84-85 watts
just after vid card output shuts down 81-82 watts. Then something i didn't expect,
a few minutes after the vid card output went off the watts dropped additionally to 72-73 watts.
When it went into "away mode" it dropped to 10-11 watts.

I will do the server later and this PC last.

stefuel · Posted: Thu Jul 04, 2013 12:07 pm Post subject:

I might be looking at 4 modes here. When running at 72-73 watts, it might be in "away mode" and the 10-11 watts might be "sleep". I will need to disable "sleep mode" if I want to stream unattended.

stefuel · Posted: Thu Jul 04, 2013 1:07 pm Post subject:

Changed my mind and did this PC next as the commercial server isn't connected to anything and is out in a smoking hot garage

I missed something in the first test that I should have looked at but didn't even notice until I plugged this one in..

This PC uses 11-12 watts just plugged in but not powered on YIKES
Powered up to a desktop and wait 10 minutes 130 watts
After vid card output shuts off 124 watts

That's it for this puppy. It uses more plugged in but shut off then the 390 does booted up in standby(with 4 hard drives).

CIR Engineering · Posted: Thu Jul 04, 2013 2:39 pm Post subject:

To me it's not just the cost either. We have more and more devices plugged in and drawing dead current all the time. It's amazing the amount of power we use for devices we aren't using at the time. Our house's dead loads have been increasing dramatically over the past 10+ years. We are wasting so much electricity...

craigr