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Five PC Power Myths Debunked
snydeq writes "Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year, according to Energy Star, savings that can add up quickly for large organizations. Yet most organizations remain behind the times on PC power management, in large part due to common misperceptions about PC power, writes InfoWorld's Ted Samson, who outlines five PC power myths debunked in a recent report from Forrester, ranging from the energy savings of screen savers, to the energy draw of powering up, to the difficulties of issuing patches to systems in lower-power states."
this article was written by a self-aware PC who is tired of the human race's waste of time and energy.
Energy is kWh power is kW. "Energy at a rate" is power, and should be in kW not kWh.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
In the winter I leave my computers on. I don't think I am "loosing" any energy that way since it's used to heat my house.
>>>"Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year"
How am I supposed to download last night's episodes of Smallville and Supernatural if I have my PC turned off during the day? Jeez. Insensitive clod. ;-)
FOX NEWS.com should be BANNED from television and internet. Have the Congress take it over and give us Truespeak.
If you spend 10 mins per day turning you pc on and setting up your work environment, and 5 mins closing everything, the cost of your time spent on this task will negate $25 saved ten times.
May Peace Prevail On Earth
Turning off PCs during periods of inactivity can save companies a substantial sum. In fact, Energy Star estimates organizations can save from $25 to $75 per PC per year with PC power management
Lets assume each PC has a user who is paid at least $25000 per year. We can clearly see the savings on the cost of that employee and thier PC setup caused by this are negligable.
he Forrester report does acknowledge that end-users have very little patience for downtime. However, it suggests that "potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management."
Complaints or not the company is paying for any user downtime.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
. . . as if millions of Folding@Home and Seti@Home clients suddenly cried out in terror and were suddenly silenced.
All through college I left my PC on 24/7, however now that I'm paying the bill I have thermal throttling and the other new power-saving standards all turned on, and I turn everything off (router, modem and all) entirely when I'm not using it. It's odd the way people look at it; at work some users say "Well I never leave it on at night because I know that it makes the computer die quicker" and some people say "Well I never turn it off because I want it to last longer." I think the truth is that modern hardware really can handle both philosophies and it's just a matter of convenience vs. power costs at this point.
"potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management."
Now that just plain hilarious.
Sites like Blackle suggest that a black screen saves energy. May have been true for CRT displays, but modern TFT Displays always have the backlight on, even on a black screen.
Learn how to save $25 to $75 by purchasing the $279 dollar report that the article is hawking. No thanks. This article has no business even being on Slashdot. It isn't news, it is an advert.
Tequila: It's not just for breakfast anymore!
1.42kw for the computer to run overnight has a cost of around 10 cents to the company.
Waiting 5 minutes for your PC to boot at the federal minimum wage of $6.55 per hour has a cost of around 55 cents to the company.
It costs the company at least 5 times as much to have you boot your PC in the morning as it does to let it run overnight.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
I agree that you can save power with low-power (standby) modes on your PCs.
However, as a network admin as a mid-sized company, I also have seen loads of frustrations where PCs (both laptops and desktops) don't come out of power save mode cleanly, requiring a reboot. Wake-on-lan is also a great concept, but also pretty buggy (again...in my limited experience trying to implement it). We also have issues where our client systems are using network applications with license pools (e.g. database applications or CAD packages). When a user leaves one of these applications open, then the PC goes into power save mode...it really freaks out when it comes back out of power save mode since the license server thought the system had released the license, but the client still thinks it has a licens in use. This situation usually results in the need to reboot, which frustrates the users to no end.
I set all of our PCs here to lock and send only the monitor into low-power mode after 20 minutes or so. Then we don't have the problems with coming out of power save mode and having locked up or frozen applications (especially the aforementioned network applictions), but still save a good bit of power by allowing the monitor to be turned off automatically.
Anyone have any idea what percentage of power is used by the monitor versus the PC itself? I don't have a clue, but I'd bet it's a pretty good percentage. There's also probably a big difference between CRT monitors and LCD monitors...again, my gut feeling, but I can't cite any numbers.
Later,
JS
WTF is with this stupid meme?
Of the four instances in which watts were referenced (directly or in compound units), three are completely boneheadedly wrong:
They should be:
You *can't* call it a typo when they are perfectly backward in three out of four incidents. And you can't call it "They just got it backward..." when they got it right once. You must conclude, therefore, that they have almost no grasp whatsoever of units.
FTA: Modern computers are designed to handle 40,000 on/off cycles before failure
With all the reboots required, that means I am limited to three Vista reinstalls?
"Myth No. 5: My PC users will not tolerate any downtime for power management.
The Forrester report does acknowledge that end-users have very little patience for downtime. However, it suggests that "potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management.""
I love this kind of response. It's pretty much ignoring the problem. PC users will not tolerate any downtime for power management even if you "educate" them. This is trying to wave the problems away and it won't work.
Knowledge is power. Knowledge shared is power lost.
Any modern PC can S3 suspend.
S3 suspend cuts power use by 95% and the PC resumes *INSTANTLY*.
I can S3 suspend my laptop and have it run off the battery for over a week - open it up and I am back where I left off in about 2-3 seconds.
There is no argument against having an IT policy MANDATING S3 suspend. Hell you can even automate it to do it by default every day at 6 PM unless the PC is in use (easily checked by screensaver APIs).
Or you could use a cron job and wake on lan to shut them down at night and start them up in the morning without affecting the worker drones at all.
When our name is on the back of your car, we're behind you all the way!
I have never had a PC or a Laptop which was able to reliably "Suspend" or "UnSuspend" Never in my life.
Not with Windows or several Linux Distros. I would say at least 25% of the time the machine will not return and must be rebooted anyway.
From my experience with some corporations, the way it works is more like:
1. The left hand doesn't know, and doesn't want to know what the right is doing. If your department can save $10 bucks, but it costs everyone else 10 million in workarounds and lost productivity, who cares? You're the greatest anyway.
2. Any attempts to rein in waste and such effects, just introduces one more layer who'll get their bonus for making you buy a tool that costs $10 less, but where you spend 100,000 more in salaries to do the same job. Occasionally it introduces a masked form of corruption too: they get more bonus for buying a $1000 pencil at 50% discount, than a normal one at 5% discount. In the former case they "saved" $500 per pencil. They're that great.
3. Don't underestimate interdepartment power games. Making you curse and waste more effort for implementing my hare-brained cost-cutting schemes, is the gretest achievement some people can get. It's me having power over you. For some people it's a powerful drug.
4. Theatre. Being seen as doing something beats doing the right thing. You can see that at all levels and in all domains: security theatre, cost-saving theatre, etc. Being seen as being teh great green saviour can beat actually saving money.
5. In that vein, beware the new boss who just has to piss on everything to mark his new territory. The higher level, the more dangerous. These guys _have_ to show that they changed something. It shows vision, leadership, etc. So he'll cheerfully make an actual loss, just so he can put a good leadership and vision theatre.
6. There's a whole caste of people across the pyramid whose goal in life is to not rock the boat and not be responsible for anything. It's better to comply with a dumb rule (even one that wasn't supposed to apply to your situation or domain) than to have anything be your personal decision, and responsibility if it fails. Applying someone else's rule is like having a papal indulgence: whatever goes wrong, you're not the one who'll be punished for it. These fine guys and gals would mindlessly enforce even turning off the computers _during_ work hours, if that's what the rules say.
7. Don't underestimate the effect of rewarding failure. E.g., see the thing about "saving" money by buying a disproportionately _more_ expensive thing. E.g., in some places, keeping the people under you from doing their job can mean needing to hire more people, and if you get enough of them you get a promotion. E.g., being the guy who dumbly applies rules without thinking, cam actually get one a promotion or at the very least it's often enough to not get demoted or phased out.
So, yes, I've seen places where they paid consultants in the range of thousands per hour, but would rather pay those to twiddle their thumbs for a quarter of an hour while a baroque configuration starts, than "waste" cents on leaving that computer idle over night.
A polar bear is a cartesian bear after a coordinate transform.
I keep wanting to just ignore such errors, calling the writer an idiot, but often the random units cause the science to be indecipherable. In this case you can figure out what they are getting at.
Any modern PC can S3 suspend.
S3 suspend cuts power use by 95% and the PC resumes *INSTANTLY*.
I can S3 suspend my laptop and have it run off the battery for over a week - open it up and I am back where I left off in about 2-3 seconds.
There is no argument against having an IT policy MANDATING S3 suspend. Hell you can even automate it to do it by default every day at 6 PM unless the PC is in use (easily checked by screensaver APIs).
I still have issues suspending/waking computers. Generally it works fine... But sometimes you run into odd issues.
One client we support has a piece of software that hates waking from suspend. Pitches a huge fit. All sorts of errors.
And I still have problems with some computers/OSes that really should handle S3 just fine simply choking on it. Won't resume reliably or whatever.
The real problem I have with power saving options is rolling out the settings consistently across multiple computers. Last time I checked (and it has been a little while since I checked, so I could be wrong) there was no way to push out power settings with a GPO. Sure, you can set screensaver options... Turn off the monitor or something... But that doesn't get you a suspended computer. You can set options on the individual computer, in their motherboard settings... But that isn't easy to update/change across a network. You can throw together a pile of scripts to shut down machines...maybe try to use wake-on-LAN to power them back up in the morning...
I'm not saying it can't be done. And I'm not going to say that you can't save any power by doing it. But there doesn't seem to be a simple way of managing these settings across a network yet. It still seems that power management is a hacked-together feature that was tacked on after the fact.
I'd love to be able to push out a group policy that made all the computers on my network suspend after an hour idle.
"Work is the curse of the drinking classes." -Oscar Wilde
I dunno about you, but I'm currently wasting some Friday!
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
It makes perfect sense. I just read it to mean that power usage increases every hour by 89 watts, and that by the time it's been left on overnight for 16 hours, the power usage of an average desktop has increased to 1.42kW. (If you think I'm joking, do the math -- that can't be a coincidence ;-))
This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW, which will probably result in it melting through your desktop unless you have very good cooling.
This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW
64kW should be enough for anybody.
Unit errors are generally a sign in technical fields that a report hasn't been well thought out. No engineer proofreading this would have missed such a blatant error which means that an engineer didn't proofread it.
If an engineer did not proofread it, an engineer did not likely do it. Therefore, the content of the article was likely done by an incompetent hack and charging $279 for the report is a way of hiding the fact that it was written by a hack.
" "Modern computers are designed to handle 40,000 on/off cycles before failure, and you're not likely to approach that number during the average computer's five to seven year life span."
Too bad all major HD manufactures claim 10,000 power cycles, and many power saving settings will turn off a HD w/o doing anything else. Which means you may have many more than 1 HD power cycle per computer power cycle.
"some studies indicate it would require on/off cycling every five minutes to harm the hard drive."
over how much time, because if you did this continuously, you would kill a harddrive in less than 35 days since you would have eat'n all 10,000 average power cycles.
I've traditionally left my machines running, to avoid thermal stress from power-cycling and mechanical wear on parts from spinning up from a dead stop. I've found the big savings comes from two things:
If I need more power savings, I might spin down the hard drives. But modern drives don't use that much power just to keep the platters spinning, most of their power consumption's driving the heads. Simply retracting the heads and not moving them lowers the drive's power consumption by a fairly big percentage, and that'll happen automatically when the system isn't accessing the disk. None of this requires any fancy sleep or hibernate or suspend magic.
I have noticed one thing, though. My Linux systems go idle fairly cleanly. Nothing's happening, minimal CPU time gets used (mainly the regular cron process waking up to check whether there's anything to run, then going back to sleep) and the hard drive stays completely idle. Windows, OTOH, keeps pinging the hard drive every 5 seconds or so even when completely idle. It's not much, just enough to make the HDD light flicker, but I don't see that with Linux. It makes me wonder how much of the "You need to put your system to sleep!" hype is simply because Windows doesn't know how to idle properly?