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The Power Saving Guide

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May 30, 2007 12:06:25 PM

You don't have to buy the latest energy-efficient PC hardware to save energy and reduce heat dissipation. Small steps already can make a difference.

More about : power saving guide

May 30, 2007 12:49:22 PM

Well did enable the feature in which to power off my storage drives if not in use in 10mins.
May 30, 2007 1:09:35 PM

that was a bad example picture for the "vista has many different power management options" lol, showing only 2..
Related resources
May 30, 2007 1:20:18 PM

"Use smaller displays instead of multiple smaller displays."

Does that statement mean to say to use one LARGER display instead of multiple smaller displays? Or use only one small display instead of multiple?
May 30, 2007 2:26:24 PM

If only we could harness the graphics card heat to cook food and make coffee
hmm?... :? Patent Pending

I like the power consumption chart, gives a general idea of the kind of PSUs these computers will need, slow moving toward having to use the Oven or Dryer power oulets to run computers... scary thought 8O .
May 30, 2007 3:46:15 PM

__Video Card_____2D__3D
GeForce 7600GT___89__131
Makes my fanless 7600GT look even sweeter 8)
May 30, 2007 4:17:48 PM

One piece of equipment I use alot is "Kill-A-Watt" off of ebaby for under $30. Very inexpensive piece of equipment to find out how much power it's consuming every hour. At first I thought my PC was using 400 watts of power and thanks to H.E. rating it's actually using 150 watts under normal load (non 3D) so I'm happy with it.

Darkk
May 30, 2007 4:26:45 PM

I've recently been toying around with powersavings. Here is a thread where I described my own success at trimming 30 watts off of my non-3d desktop use. These power savings also have the added benefit of lower idle temps.

I've tested my system with just the computer plugged into the power meter and my UPS plugged in. My UPS has my monitor, router, cable modem and computer plugged in it. When my computer is off I'm still using 33-35 watts for the power to the computer, router, cable modem, monitor standby and ups. I think the ups is large part of it but I like using a ups for the safety and also because it cleans up the power from the wall.
May 30, 2007 5:05:49 PM

You forgot to mention screen brightness. If you lower the brightness on your monitor it saves power. So re-arranging a few things in your office to keep glare off your screen can save some electricity while also reducing eye strain. It's a common feature on laptops to have power saving features that adjust screen brightness. Would be nice to have that power savings quantified.

You also didn't bench the X1950 PRO. It's supposed to be a more energy efficient core.

Overall I would say it's an ok article. I do take issue with the "but it won't save much money so why bother when it really comes down to it?" attitude. If we save electricity first we can avoid having higher electrical rates which would disproportionately impact poorer people and cause me to have to save power in ways I don't want to if rates get too high. It's not just our computers that we'll start turning off if energy rates were to, for example, triple. It's our heat, AC, hot tubs, swimming pools, water heaters would be turned down, showers would be shorter... all these things that make our day-to-day lives pleasant. I don't want that and you shouldn't want it either so let's all do a little now, whether it makes a big difference on our monthly electric bills or not, so we can buy time to roll out new technology and energy sources and avoid a *real* power crunch. Don't say it can't happen, there are plenty of places in the world where it's happening already. If you're whining about things like buying CF light bulbs now because they can take 1-3 years to pay for themselves what makes you think you'll be happier about it when they can pay for themselves in 4-12months because the electrical rates have gone up??? 1-3years is a perfectly acceptable period for an investment to pay back. Maybe this doesn't apply to a computer that you only plan on keeping for 6-18months but realize the numbers for what they are, not some misguided concept that if it doesn't pay for itself in a few months it's not worth it.

I like using electricity. I use gobs of it :twisted: I live in Washington with some of the cheapest electrical rates in north america (and Seattle Electric is greenhouse gas neutral for whatever that's worth). I like this situation and I don't want it to change!

I just build my first solar cell this weekend for a cost of $15 :)  Just a little one but a fun project that I think us geek types could really dig into. I used it to charge up some AA and AAA Ni-MH cells (for my cordless keyboard and mouse. I mostly got tired of having to run to the store when I needed new batteries) and to power the TFT display from my DIY projector I made and used it with ambient light. Next project is to build an LED lamp and see if it can run for 4+ hours a day with enough brightness to matter.
May 30, 2007 5:15:30 PM

Thems a whole lot of words just to tell me to go into stand-by whenever possible.
May 30, 2007 5:26:05 PM

Quote:
Thems a whole lot of words just to tell me to go into stand-by whenever possible.


We're geeks. We don't do something just cuz they tell us too :p 

You were also supposed to glean the suggestion that when choosing components, at least when you're buying new hardware anyway, you should consider energy consumption as inefficient devices can cascade into AC cooling load, case cooling cost, component life expectancy reduction and noise pollution problems and "suspend" doesn't really cover any of those points.
May 30, 2007 6:34:11 PM

Pretty good article -- nice reminders for us who are looking for new hardware parts.

This just makes me want to move away from CRT even more. Ugh, this room is always the hottest in the house, I'm betting a more efficient screen would help lower my room temps a bit.
May 30, 2007 6:36:27 PM

Another way to conserve power.....turn the dang thing off when you are not using it. :wink:
May 30, 2007 7:40:11 PM

I think that considering how frequently people go through computers - especially the enthusiasts - the easiest thing to do is to make sure you get a high-efficiency PSU. My media centre's PSU from SeaSonic is around 80% efficiency, which is much better than the "industry average" 65%. It can easily make sense to pay a few extra bucks for a high efficicney PSU.

Otherwise, if you're running at stock frequency, CPUs can usually be undervolted. I've shaved about 8W (load) off my X2's consumption by going from 1.2V to 1.1V. I might try getting as low as 1.0V and seeing if it's still stable. I imagine the same can be tried with GPUs and memory.

I really want to get a watt meter and see just how much my computers use - both idle and when running folding@home. I think my media centre, with a high-efficiency PSU, undervolted X2 3600+, and integrated graphics probably takes about a third or less of the power as my desktop with an older PSU, discrete graphics, and an overclocked PD820. The latter computer definitely heats up the room in the summer (not such a bad thing in the winter though).
May 30, 2007 8:21:12 PM

I agree with the above post, but am not sure that THG included anything on PSUs.

Suppose your PC requires 400W at load, that is 350W coming out of the PSU.

HE 80% under load requires 500W at the wall (what you pay for).
Avg 65% efficiency requires 615W at the wall.

Save 115W by going to a higher efficiency PSU. Simple! Why bother with replacing a HD to save 10W...

For those of you in the UK, the 230V PSUs can reach 90%, whereas 120V US PSUs can only do 80-85 tops. I would venture a guess that no name PSUs are around 55% or so.
May 30, 2007 8:24:56 PM

Quote:


I really want to get a watt meter and see just how much my computers use - both idle and when running folding@home. I think my media centre, with a high-efficiency PSU, undervolted X2 3600+, and integrated graphics probably takes about a third or less of the power as my desktop with an older PSU, discrete graphics, and an overclocked PD820. The latter computer definitely heats up the room in the summer (not such a bad thing in the winter though).


Canadian Tire has a watt meter for 24.99. I don't know if the link will work the way their site works.
CDN tire watt meter
May 30, 2007 8:28:13 PM

Quote:


I really want to get a watt meter and see just how much my computers use - both idle and when running folding@home. I think my media centre, with a high-efficiency PSU, undervolted X2 3600+, and integrated graphics probably takes about a third or less of the power as my desktop with an older PSU, discrete graphics, and an overclocked PD820. The latter computer definitely heats up the room in the summer (not such a bad thing in the winter though).


Canadian Tire has a watt meter for 24.99. I don't know if the link will work the way their site works.
CDN tire watt meter

24.99 USD at xoxide.com http://www.xoxide.com/p3-kill-a-watt.html
May 30, 2007 8:31:55 PM

I think it's time to go shopping. :) 
May 30, 2007 11:42:24 PM

I thought a good power bar also cleans the power to the computer.

I thought the only difference between a UPS and a good power bar is the battery backup.


unless i am mistaken
May 30, 2007 11:47:16 PM

You've got me there, I honestly am not certain. I'd have to research it but I don't know how a power supply can compensate if the power dips like a brown out.
May 30, 2007 11:48:51 PM

My power board is some cheap $20 one, doesnt cause me problems.
May 30, 2007 11:58:57 PM

I dont want to get off topic with the UPS vs powerbar. That would be a good toms article though to clarify what the differences are and exactly what kind of protection they provide.

My dfi board with barton sempron proc has a jumper to force the fsb from 133mHz to 100mHz. I wonder if the system will run cooler this way. I dont know any other way to cool down these older systems.

cheers all
May 31, 2007 12:14:49 AM

Quote:
I thought a good power bar also cleans the power to the computer.

I thought the only difference between a UPS and a good power bar is the battery backup.


unless i am mistaken


A surge protector with RF filters will not protect you from brownouts and voltage spikes will likely cause it to simply turn off. Also, the power coming from the inverter of a UPS is not necessarily very clean. It takes extra circuitry and filters to make it clean that not all UPSs have. And, of course, all those extra circuitry and filters to clean up the power and the inverter itself all reduce efficiency.

The really good solution is to eliminate the inverter and run the computer directly off DC voltage (ex: 12v). Maintaining clean voltage supply then becomes much easier and the UPS and the PSU are both a lot more efficient. I don't think there are any products for this available that are targeted at consumers though. Intel was talking about it for data centers an IDF or two ago. I'm going to try and make one since I can use my solar array to provide some of the power.

For a low-end computer drawing <50w on average being used ~8hours a day you could power it off a <$300 +45w solar system and never have to plug in again (at this point you wouldn't have a "UPS" you'd have "a battery with solar panels hooked up to it"). At that rate it would take about 20 years to pay for itself vs. plugging it straight into the wall (400wh per day at $0.10 per kWh USA average). If you factored in another 25% efficiency for a 12v PSU and a small voltage regulator/monitor instead of a UPS you're still looking at ~15years with the potential of a cloudy week seriously cramping your style. Yeah, photovoltaics kinda suck at cost efficiency right now but I don't think more expensive grid electricity is a good solution to that problem. Saving electricity so we don't have to buy really expensive power generation systems is a much better plan :) 
May 31, 2007 1:02:16 AM

Quote:
I thought a good power bar also cleans the power to the computer.

I thought the only difference between a UPS and a good power bar is the battery backup.


unless i am mistaken


I think what you're thinking of is either a power conditioner (commonly used for home theatre systems to allow the cleanest sound and picture - I have one by Monster) or a voltage stabiliser. The latter use either large capacitors or batteries, but are quite different from a UPS.
May 31, 2007 2:38:52 AM

Seen quite a few good articles by Schmid and Roos lately, and this is one of them. Good for insight, if nothing else. People tend to overlook the impact of things like power consumption in areas other than how long their laptop-battery lasts.
May 31, 2007 8:34:34 AM

i always buy motherboards with onboard graphics, so i can downgrade them into secondary computers when i upgrade while still keeping my expensive graphics card for the new machine or reselling the card to add a discount to the new build. i wish desktops could switch to integrated graphics while in 2D and pci-e for 3D like a laptop i read about recently. that would save 100W easily on my desktop. but, you're right that psu's are probably an even bigger waste hog that they didn't bother getting into.
May 31, 2007 10:01:21 AM

Good Toms, but still not approaching SilentPCreview in terms of depth...

I'd rather see common tweaks like rmclock / crystalcpuid and rivatuner/nibitor that will take the numbers for the cpu/gpu to a new low with undervolting/LOW 2dspeeds while max p-state/performance 3d is still in full speed for noperformance cost.

My 90nm Windsor does 217x5 (lowest p-state) at 0.8volts 24/7 and highest at 217x12 @ 1.275 Vcore (overclocked but with CnQ IS possible for the nah sayers)

my 8800gts is running at rivatuner's 2d speed of 285/700core/shader & 485mhz mem which will let the card idle at 58degrees in vista aeroglass with room temp at 32*Celsius (tropics) Cpu Idles at 36-38 for the cores (cnps9500nt)...


I wonder when the bigger sites will start doing this for an article

also if someone knows what the Alt. Vdimm/clock options in the bios gives for real world results let me know.
May 31, 2007 12:00:38 PM

I used to build desktop systems using mobile Athlon chips (I hate wind tunnel machines!), but when the intel iMac's came out I gave up on building a faster, quieter system. My 20" imac runs 2W when it is idle, and 65-75 watts when I'm using it. I've never seen more than 85W, although I've heard of people getting them up to 90W. It is nearly silent, and under load the fans crank up to very quiet (less noise than my old tower with custom cooling made under my desk, not right in front of me!). I think the future of computers is really going to be similar designs, as you can't beat it. Now, if you can't live without a top of the line (or even mid range) graphics system, you are going to need to burn 3x the power (and 15x at idle) and build a custom desktop. There is always going to be a small margin of the market on that bleeding edge. Personally, I can live without the fastest cards out there and stay 1.5 years behind the curve on game releases.
May 31, 2007 12:20:19 PM

Quote:
Thems a whole lot of words just to tell me to go into stand-by whenever possible.


We're geeks. We don't do something just cuz they tell us too :p 

You were also supposed to glean the suggestion that when choosing components, at least when you're buying new hardware anyway, you should consider energy consumption as inefficient devices can cascade into AC cooling load, case cooling cost, component life expectancy reduction and noise pollution problems and "suspend" doesn't really cover any of those points.

First off, your whole scenario of electricity becoming extremely expensive would probably never happen, except in a short-term scenario, as in what happened in California years ago. Electric companies are in it for the business - to make money. If you increase the price of electricity too high, people will make the initial large investment of solar energy, and then almost always get their electricity for free.

Electric companies don't want this. They need to keep their prices reasonable so people don't take that step of spending 5-10 grand (guess) to then get their own power for free. At the same time, those that can afford the currently expensive price will cause production of solar panels to go up and the price will go down, making it affordable for more people.

Now to the quote:

How does not placing your computer into suspend mode NOT cover all the points mentioned? On average, most high-end users leave their computer on 24/7. 90% of the time, that computer is probably sitting idle. If every high-end user placed their computer in suspend, they'd each be saving close to 200 watts. This is better savings than any energy efficient component could achieve!

In addition, suspend will not increase house heat and cause AC load, it will increase component life and it will reduce in noise pollution.

My point: at no cost to the user, suspend would be the best thing they can do to reduce the power consumption of their system. Don't knock the suspend mode :) 
May 31, 2007 5:24:16 PM

Quote:
Thems a whole lot of words just to tell me to go into stand-by whenever possible.


We're geeks. We don't do something just cuz they tell us too :p 

You were also supposed to glean the suggestion that when choosing components, at least when you're buying new hardware anyway, you should consider energy consumption as inefficient devices can cascade into AC cooling load, case cooling cost, component life expectancy reduction and noise pollution problems and "suspend" doesn't really cover any of those points.

First off, your whole scenario of electricity becoming extremely expensive would probably never happen, except in a short-term scenario, as in what happened in California years ago. Electric companies are in it for the business - to make money. If you increase the price of electricity too high, people will make the initial large investment of solar energy, and then almost always get their electricity for free.

Electric companies don't want this. They need to keep their prices reasonable so people don't take that step of spending 5-10 grand (guess) to then get their own power for free. At the same time, those that can afford the currently expensive price will cause production of solar panels to go up and the price will go down, making it affordable for more people.

Now to the quote:

How does not placing your computer into suspend mode NOT cover all the points mentioned? On average, most high-end users leave their computer on 24/7. 90% of the time, that computer is probably sitting idle. If every high-end user placed their computer in suspend, they'd each be saving close to 200 watts. This is better savings than any energy efficient component could achieve!

In addition, suspend will not increase house heat and cause AC load, it will increase component life and it will reduce in noise pollution.

My point: at no cost to the user, suspend would be the best thing they can do to reduce the power consumption of their system. Don't knock the suspend mode :) 

Nice economic theory there. Now back it up with facts from what is actually happening in the real world. Even in the USA right now the disparity in electrical rates is at a factor of 3. http://www.eia.doe.gov/cneaf/electricity/epm/table5_6_b... Hawaii: 22.06, Connecticut: 18.43 (ok, so Hawaii is a small island chain, so here's second place), North Dakota: 6.26. Electrical rates soaring to 3x what they are is impossible, huh? For some people they already have. And that's not even looking at the rest of the world where some electrical rates are even higher. Expanding fossil fuel and hydro production facilities is not feasible (and environmental protection is only one of the reasons, the good hydro spots have already been taken and fossil fuel markets have become increasingly volatile and expensive). Your grade school level understanding of economic theory and blind faith that as long as greed and competition are involved that everything will be ok are no substitute for the facts of what is really happening. Also... there isn't any real competition in the energy market anyway. There's only one set of wires going to your house, you can't choose to buy from a competing provider so the gods of capitalism that you put so much faith in can't save us here. That's why we have to do more than "vote with our dollars". That's why things like Energy Star exist: to control the demand for electricity without regard to free economy, because there isn't a free economy on grid electrical supply.

Now on to your response about suspend: because as soon as you take the computer out of suspend you have all of those problems; suspend didn't solve them. I listed a bunch of problems OTHER than saving electricity.
May 31, 2007 6:15:51 PM

There is continued development in hydro power here in Quebec, which already has the cheapest electricity in, well, the world as far as I know - something like 4.5 cents/kWh. I belive most of the new development is to satisfy export demand to NY, etc.

I'm amazed at the high price of electricity in some places. I think the case for solar power becomes very good around 25 cents/kWh. Wind has come down to as little as 4 cents/kWh, but it's highly dependent on location. Where I live, I see trucks hauling wind power turbine blades (huge ones!) all the time. I'm not sure where they're going - export or to elsewhere in Canada, but there sure is a lot of wind power development.

I really hope for cheap solar in the long run. I imagine a future where homes are mostly self-contained for power using DC - much more convenient for electronics.

As for competition in the current market, it's true that the distribution of electricity is a natural monopoly (and, so, poorly fit for capitalism). However, there is opportunity for competition in power generation. Some places allow you to choose your generation company (such as selecting "green" power, etc.). The juice that comes to your house isn't the same as the company's you've selected, but the power delivery system can place demand to generation stations according to customer choice.
May 31, 2007 7:02:16 PM

Did I miss it or did the article not address the fact that most enthusiast's speaker systems can consume a whole bunch of watts as well. I know that my Logitech 5500 system is rated at 100 watts. Granted, I'm not running it at that sound level, but it does dissapate quite a bit of heat. So much so, that I've been turning it off when not needed (haven't put in the AC window units yet).

There should be a usb connector to the speaker controller that puts the amplifier in standby as well...get on it Logitech!
May 31, 2007 7:12:44 PM

This is a good idea, based on the assumption that the amp in your computer's sound system is Class-A. If it's Class-B or even D, then the power consumption is related to the amount of sound coming out of the speakers.

And as far as being rated as 100W, that might be what your speakers are rated at, but that's certainly not what the amp inside is rated at. I've seen some incredibly cheap 100W sepakers. It takes less than 10W to make a lot of noise. Even very inefficient speakers should be in the 80 dB/W range (my main speakers are 95 dB/W).

My stereo amp gets hot, as it's Class-A - the power consumption is a function of volume setting, not the actual sound signal. However, my computer speakers never even feel warm.

Still... a digital sound signal connection that includes power switching would be a nice feature - and you might as well throw in turning the speakers off for standby or during times when no sound has been played for a certain time.
May 31, 2007 7:35:50 PM

Good points HotFoot. I wasn't aware that Les Québécois were building new hydro. Here in western USA serious consideration towards taking out smaller dams is being discussed. Can't get much electricity out of a mere 10-20ft drop but the cost to maintain and run them are still huge. Whether or not this is a good idea seems to vary greatly on a case-by-case basis (there's some wacko movement in California trying to take out some major reservoirs for instance, probably a bad idea). They are also deploying wind turbines like crazy in eastern Washington which is kinda cool but the power company seems to think they are entitled to slap them down anywhere they want... including IN a bird sanctuary near Ellensburg, WA.

Certainly at >$0.25/kWh, slight advancement in technology, some sort of smallish rebate program, and a sunny location a solar installation could pay for itself in 5 years and quickly save you money on the cost of buying a home. Some places aren't very sunny though and for people who couldn't afford the upfront cost they would just be stuck paying high electrical rates. Better to try and keep grid electricity as cheap and green as possible for as long as possible while the cost of photovoltaics goes down and the efficiency goes up (which really are the most convenient easiest way to generate power once installed, but they are expensive and something like only 12% efficient).

Home electric generation with native DC-powered devices really would be convenient though. You'd have multiple sources of power and maintaining a steady DC current is much easier and cheaper than conditioning AC power sources. Last winter western washington was hit by a smallish (almost category1) windstorm and some customers were without power for 2 weeks. Several million people were without power for 3 days or more. People were actually so unprepared to deal with a power outage that there were dozens of deaths and hundreds hospitalized. I was personally without power (zOMG no internet!) for 8 days, but thankfully I had a gas water heater and stove. I've lived in places where power disturbances have destroyed some of my electronics too. If I could generate most of my own power and just use the grid for backup and peak usage it would be most convenient indeed :)  But first I need to be able to afford it and more expensive grid electricity doesn't make solar panels cheaper :/  However, the less electricity I use the more viable it is to generate my own power. If I wanted to I could use zero electricity... but I don't want that or anything even close to it xD

Devices and habits that give me the same or greater amount of pleasure while using less electricity with an upfront cost that is defrayed within a few years is definitely where it's at for the foreseeable future. If everyone is a little bit conservative and the rabid anti-environmentalists STFU for a bit (how they seem to get off on polluting and wasting as much as they can just to piss off people who are concerned about our shared fate is really astounding) we should be able to defray any major economic or environmental backlash so we can develop better technology to deal with the problem.

Suspend and/or turning it off when not in use can work quite well in some situations. I think GFX cards need to dynamically clock themselves down when not in use like CPUs do. Also, I think PSU efficiency should be required to be advertised prominently much in the same way it is required for household appliances.
May 31, 2007 7:51:32 PM

It all comes down to common sense. Sometimes the economic analysis requires a little finesse and forward-thinking, but in the end we're talking about hard numbers. Regarding environmental motivations, I believe in a moderate conservative approach. My next car will be somewhat more efficient than my current one, but I'm not going through one car a year just to keep up with the latest MPG craze - same deal with computers. I'll be building my next desktop to consume about half the power of my current one, but that's not hard considering my current one is built around an overclocked Pentium D. :wink:

One example of common-sense is a little study (sorry, no link) that showed that a large estabilishemt such as a University would save a tremendous amount of money by employing someone to go around turning off the computers in all the different labs at night. I'm not sure why they don't have these computers set to standby/hibernate in the first place, but in any case the study showed that even at very low electricity costs, someone could be paid a full-time wage to just go around turning off the computers at night and then on again in the morning.
May 31, 2007 7:52:03 PM

Quote:

Still... a digital sound signal connection that includes power switching would be a nice feature - and you might as well throw in turning the speakers off for standby or during times when no sound has been played for a certain time.


I think a SPDIF receiver should be able to accomplish this without too much difficulty. They would have to add some logic and additional buffers though. Would be kind of weird to have a ~500ms delay followed by 1000ms of the sound playing at double speed every time woke up your receiver. I wonder how long it would actually take to wake up a receiver from suspend and start playing sound... If they could do it in <100ms you probably wouldn't notice much. I wonder how much it would add to retail cost once mass produced... a couple dollars? Interesting idea.

I wonder if this could also be implemented on an embedded level. Turn off all the logic circuitry for audio playback when not in use in addition to any analogue amplifiers?
May 31, 2007 8:54:40 PM

Quote:
Did I miss it or did the article not address the fact that most enthusiast's speaker systems can consume a whole bunch of watts as well. I know that my Logitech 5500 system is rated at 100 watts. Granted, I'm not running it at that sound level, but it does dissapate quite a bit of heat. So much so, that I've been turning it off when not needed (haven't put in the AC window units yet).

There should be a usb connector to the speaker controller that puts the amplifier in standby as well...get on it Logitech!


You are onto something here. I just plugged my computers speakers into the watt meter. They are nothing impressive but probably typical for the average user; I have a wife and kids, big computer speakers would be wasted.
Altec Lansing ATP3, 30 watts RMS, 2.1 set.

These speakers are pulling 10 watts from the wall just for being plugged in. When I turn the volume down to zero the LED on the front goes out leading me to believe they are turned off. They still pulled 9-10 watts!
On the plus side I just tried them at about 70% volume playing White Stripes, Icky Thump,(bass heavy), they fluctuated between 4-19 watts. At high volume they dropped to 4 where at standby they never went below 9.
May 31, 2007 9:48:09 PM

What would have made this article a lot more appealing to me is if the writer would have given us an understanding of exactly how much wattage is worth. He gives no cost analysis to show that it is worth consuming 50, 80, 100 less watts. And when I started to always place my computer in stand-by and hibernation, instead of leaving it on 24/7 with no stand-by or power saving, I never even noticed a large enough difference on my electric bill. My usage is still about the same per hour as it was prior - and I probably only have the computer on an average of 3 hours a day. My computer pulls a lot of power, as well. It's a high-end C2D system that can run FEAR and BF2 over 80 FPS average. In the summer I pay 7.976 cents per kWh.

I never even thought of how much wattage my Klipsch ProMedia Ultra 5.1 might be pulling. When playing music they probably use more wattage than my computer on idle. It has a BASH amp rated at 500 watts with 60/watts per channel for the 5 satellites and 170 watts for the 2x8" subs. It may be high in wattage but damn it sounds good and worth the electric cost to me ;)  If there is even a noticeable difference, which I haven't been able to see.

A year ago I started to always turn my speakers off after I noticed that my amplifier on the sub box was warm to the touch even when no sound was being sent to the unit. I wonder how many watts that speaker system uses while idle. I wonder how many watts my 700-watt JVC receiver uses while in standby mode. Might have to get a wattage meter just to stem my curiosity :) 
May 31, 2007 10:39:22 PM

A bit of an intro about how to calculate the cost of electricity would have been nice.


http://michaelbluejay.com/electricity/cost.html
(he has a lot of articles about electricity that seem fairly well written for a layman audience)

http://www.eia.doe.gov/cneaf/electricity/epm/table5_6_b...
(or, of course, your utility bill)

That pretty much covers it I think.

So 50watts saved on a system that runs 24/7 is worth $43.6248 per year at national average rate. On a system that runs 4 hours a day it's $7.2708... not so impressive.

I am very encouraged by how many people have taken enough interest in this article to post comments. I hope they do more in the future.

*edit* really bad math! fixed
June 1, 2007 3:25:42 AM

Quote:
I used to build desktop systems using mobile Athlon chips (I hate wind tunnel machines!), but when the intel iMac's came out I gave up on building a faster, quieter system. My 20" imac runs 2W when it is idle, and 65-75 watts when I'm using it. I've never seen more than 85W, although I've heard of people getting them up to 90W. It is nearly silent, and under load the fans crank up to very quiet (less noise than my old tower with custom cooling made under my desk, not right in front of me!). I think the future of computers is really going to be similar designs, as you can't beat it. Now, if you can't live without a top of the line (or even mid range) graphics system, you are going to need to burn 3x the power (and 15x at idle) and build a custom desktop. There is always going to be a small margin of the market on that bleeding edge. Personally, I can live without the fastest cards out there and stay 1.5 years behind the curve on game releases.


I call error.... 2W idle for a Merom or a Yonah comp with a 20" lcd. The LCD itself must use at LEAST 50w.
June 1, 2007 3:30:47 AM

He must have meant 2W when the system was in standby or hibernate - certainly with the monitor in sleep mode.

Just a single cooling fan in the system should be more than 2W.
!