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Is It Worth Investing In a High-Efficiency Power Supply?

samzenpus posted about 2 years ago | from the getting-your-money's-worth dept.

Power 328

MrSeb writes "If you've gone shopping for a power supply any time over the last few years, you've probably noticed the explosive proliferation of various 80 Plus ratings. As initially conceived, an 80 Plus certification was a way for PSU manufacturers to validate that their power supply units were at least 80% efficient at 25%, 50%, 75%, and 100% of full load. In the pre-80 Plus days, PSU prices normally clustered around a given wattage output. The advent of the various 80 Plus levels has created a second variable that can have a significant impact on unit price. This leads us to three important questions: How much power can you save by moving to a higher-efficiency supply, what's the premium of doing so, and how long does it take to make back your initial investment?"

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The Maths (4, Informative)

Press2ToContinue (2424598) | about 2 years ago | (#42282227)

new efficiency @ load % - old efficiency @ load % = delta%
integrate over time (delta%*cost kw/hr) until result = new unit cost (solve for t)

Re:The Maths (1)

Anne Thwacks (531696) | about 2 years ago | (#42282247)

Or don't: it comes out at several tens of years in any realistic scenario.

Re:The Maths (0)

Anonymous Coward | about 2 years ago | (#42282429)

... but you'd also have to factor in the price difference. If the prices are the same, the savings begins immediately.

Re:The Maths (5, Insightful)

SJHillman (1966756) | about 2 years ago | (#42282501)

Not to mention reduced heat output (and potentially less fan noise due to lower heat), important in many scenarios

Re:The Maths (4, Informative)

hawguy (1600213) | about 2 years ago | (#42282887)

Not to mention reduced heat output (and potentially less fan noise due to lower heat), important in many scenarios

Plus you have to add in costs due to the extra air conditioning load in the summer time (gotta remove all of that heat), and subtract in the winter time to account for the fact that your furnace needs to do less work to keep your house warm.

More maths (2)

Taco Cowboy (5327) | about 2 years ago | (#42282717)

The info I got from the article at http://www.cameralabs.com/PC_Hardware_reviews/Power_supply/Choosing_a_PC_power_supply.shtml [cameralabs.com] is this ---

If your computer consumes X-watts, it's advisable to fit a PSU that can pump out almost 2X the wattage.

Re:More maths (5, Informative)

AdamWill (604569) | about 2 years ago | (#42282849)

That was true in the past when the PSU wasn't a particularly valued component and the industry standard method of rating their power output was 'think of a number, any number. Now write that number on the side.'

It's *less* true these days if you're buying from one of the decent brands. The numbers they write on their spec sheets actually bear some kind of resemblance to reality, these days: you can actually accurately spec up your expected draw against the capabilities of a PSU and expect it to more or less work out. It's worth leaving a bit of safety room, but you don't really need 2X.

Re:More maths (3, Funny)

hamster_nz (656572) | about 2 years ago | (#42282905)

Hey! That's the same formula for calculating swap space! Must bee something deep going on here. :-0

Re:More maths (5, Interesting)

sdguero (1112795) | about 2 years ago | (#42283009)

I used to test server and PC power supplies for a living (until 2009). I do NOT recommend running at 50% load unless your PSU is a cheap turd and you are worried (rightfully so) about component failure. 80-90% load will give you better efficiency, a higher power factor, and less harmonics. Fyi, as a residential electricity customer you don't really have to worry about power factor or harmonics much but large companies can be charged by the utilities for abusing the infrastructure with a ton of shitty/under-utilized PSUs. Since the company I used to work for sold into enterprise, we were very interested in PSU performance and matching up components for efficiency.

At home, I run a decent 350W PSU now, and my system draws about 200W of DC power under load (i.e. gaming) with my components (single Intel 2500K CPU, 8GB RAM, ATI 7870 GPU. 1 HDD and 1 SSD) and around 130W when surfing the web or working. I literally couldn't find a decent, well priced PSU with lower DC power output when I built the machine 18 months ago. It cracks me up when I see guys putting 700W power supplies into their gaming rigs that never draw more than 300W (and none seem to understand the difference between AC power draw from the wall and DC power draw of the components in their system, which is what the PSUs are rated for). It's basically flushing money down the toilet in multiple ways.

Just my $0.02...

Re:More maths (1)

Bengie (1121981) | about 2 years ago | (#42283071)

It cracks me up when I see guys putting 700W power supplies into their gaming rigs that never draw more than 300W (and none seem to understand the difference between AC power draw from the wall and DC power draw of the components in their system, which is what the PSUs are rated for). It's basically flushing money down the toilet in multiple ways.

About sums it up for me. Time and time again, reviews show "at the wall" power draws for modern non-OC'd, non-dual GPU high end desktops being under 300 watts at peak.

Re:More maths (1)

sdguero (1112795) | about 2 years ago | (#42283131)

Yup. And at 80% efficiency, 300W at the wall means the components are only pulling 240W of DC power...

Re:The Maths (5, Informative)

Carnildo (712617) | about 2 years ago | (#42282461)

Or don't: it comes out at several tens of years in any realistic scenario.

Scenario 1: an always-on computer running near-idle for four years.

Idle power draw, 85% efficient PSU: 66 watts
Idle power draw, 80% efficient PSU: 70 watts
Delta: 4 watts
Total power difference over the four-year life of the computer: 140 kilowatt-hours.
At 5.5 cents per kilowatt-hour (cheapest power in the US), building with a more-efficient power supply makes sense if it costs no more than $7.70 beyond what the less-efficient power supply does.

Scenario 2: an always-on computer running Folding@Home for four years using both CPU and GPU.

Power draw, 90% efficient PSU: 215 watts
Power draw, 80% efficient PSU: 245 watts
Delta: 30 watts
Total power difference over the four-year life of the computer: 1.05 megawatt-hours.
At 36 cents per kilowatt-hour (most expensive power in the US), building with a more-efficient power supply makes sense if it costs no more than $378 beyond what a less-efficient power supply does.

The second scenario represents someone running F@H on a modern high-end computer in Hawaii -- not exactly "unrealistic".

Re:The Maths (0)

Anonymous Coward | about 2 years ago | (#42282567)

I wouldn't call a computer that uses 250 watts with high load on the GPU "high end"...

Re:The Maths (1)

Bengie (1121981) | about 2 years ago | (#42283107)

Ignoring the dual GPU video cards, the "high end" GPUs are pulling around 130watts peak. CPUs are around 125watts peak, so 255watts about represents a $1.5k-$2k 8-12 thread AMD7870 computer.

But..but...but.. dual GPUs... Well, I can purchase an 8 socket AMD and cross-fire 8 GPUs, but I wouldn't consider that a "desktop". Dual GPUs is like extreme enthusiast.

Re:The Maths (1, Troll)

Platinumrat (1166135) | about 2 years ago | (#42283111)

I'd like to add to the above. It truly depends on circumstances.

If you're trying to be energy neutral or positive in your living (e.g you want to be off the grid with a wind/solar setup) then every efficiency gain will more than offset the cost of producing / storing the power required).

If you're just wanting to view movies / ebay / email an live in a McMansion, with the full home theater setup, then there's no point because the rest of your lifestyle says "Fuck the planet, I'm all right"

Re:The Maths (-1)

Anonymous Coward | about 2 years ago | (#42282525)

Or don't: it comes out at several tens of years in any realistic scenario.

I've done this math for my 24/7 HTPC server. If you consider that energy in North America costs around $0.12/kWh, then 1 W of power consumed all year = 24 * 365 / 1000 * $0.12 = $1.05. An average HTPC server will consume around 350W (at the output of the power supply) at steady state. If you assume an efficiency of 75%, the total AC mains power jumps to 466W. At 85% that number is 411W. The net difference is about 55W, which at $1.05/W = $57.75 of energy savings per year. As such you can buy just about any power supply you want if you expect a payback period of around 2-3 years (a more than realistic time-frame for a power supply).

Re:The Maths (4, Insightful)

FrankSchwab (675585) | about 2 years ago | (#42282661)

Your HTPC server consumes 350W? What the hell do you have in that thing?

Mine consumes less than 65W running full blast, serves files and 1080p video. I'd say you'd save a hell of a lot more money by downsizing that HTPC rather than just getting a more efficient power supply.

Re:The Maths (0, Insightful)

Anonymous Coward | about 2 years ago | (#42282881)

Don't sweat it. He's an idiot who thinks that because his HTPC has a 350W power supply that it uses 350W at all times.

Re:The Maths (1)

Jah-Wren Ryel (80510) | about 2 years ago | (#42283225)

Your HTPC server consumes 350W? What the hell do you have in that thing?

What is an HTPC server? What makes it different from a regular server?

I used to run a 24 disk raid box 24x7 for media-serving duties and it pulled about 350W at steady state according to my Kill A Watt. [p3international.com]

IMG Tag? (0)

Anonymous Coward | about 2 years ago | (#42282295)

I tried to include an image of the formula using the IMG tag instead of text, but it wouldn't display. :( Any tips on how to include an image in a comment on /.?

Re:IMG Tag? (5, Funny)

feedayeen (1322473) | about 2 years ago | (#42282419)

I tried to include an image of the formula using the IMG tag instead of text, but it wouldn't display. :( Any tips on how to include an image in a comment on /.?

I've never seen an image in a slashdot comment before, I think it's for our own safety.

Re:IMG Tag? (5, Insightful)

evilviper (135110) | about 2 years ago | (#42282471)

The real embarrassment is that /. has never supported basic tags like <sup> which would allow proper math mark-up. Instead we get all manner of mangled, unreadable blobs for comments.

Re:IMG Tag? (0)

Anonymous Coward | about 2 years ago | (#42282659)

Why waste your time when over half the comments for any post are spam, trolls or star wars memes?

Re:IMG Tag? (1)

BlueRaja (1397333) | about 2 years ago | (#42282631)

Not sure why this is moderated as "funny," since it's true - <img> tags can be/are used in XSS and CSRF attacks. In fact, SVG images can contain executable javascript. And let's not even mention the possibility of polyglots: http://www.thinkfu.com/blog/gifjavascript-polyglots [thinkfu.com]

Re:IMG Tag? (1)

BlueRaja (1397333) | about 2 years ago | (#42282651)

Oh yeah, and images can be/are used for tracking as well.

Plus, if we allowed images, I'm pretty sure 90% of it would end up being porn and cat pictures.

... porn and cat pictures ...? (2)

Press2ToContinue (2424598) | about 2 years ago | (#42282935)

Are you saying this would make /. somehow a lesser site? (scratches head)

I would insert a picture of a naked cat looking quizzical here, but alas, no IMG tag support.

See what you're missing?

Re:IMG Tag? (2)

puppetman (131489) | about 2 years ago | (#42282693)

And you can thank goatse.cx for that. I can't imagine looking at that gaping hole a dozen times per day.

Re:IMG Tag? (1)

TubeSteak (669689) | about 2 years ago | (#42282763)

I've never seen an image in a slashdot comment before, I think it's for our own safety.

I remember the good old days before the spam filter when every third post was an ASCII depitction of goatse and we liked it!

Re:IMG Tag? (0)

Anonymous Coward | about 2 years ago | (#42282853)

You could make an ASCII art version of the text formula that you wanted to display...

Re:IMG Tag? (1)

Deltaspectre (796409) | about 2 years ago | (#42282451)

First let's do a sanity check. Have you ever seen an image in slashdot comments?

Re:The Maths (1)

slashmydots (2189826) | about 2 years ago | (#42282577)

I did things slightly different. Btw you didn't think this was a bitcoin story....BUT IT IS! lol. My bitcoin rig ran at 550W and I had these calculations down plus an actual meter and they were all spot on. But let's say it's my gaming computer instead. That's around 240W peak of actual device pull. Let's say it's used for 6 hours a day at max load. Let's say I was going to get a piece of crap 76% efficient one but I went with an 80+ bronze which happens to be 83%. That's 40.8 watts added in waste heat to the efficient one and 57.6W in waste heat from the inefficient one for a difference of 16.8W so times 6 hours and 365 days, that's 36KWh added per year. US electricity varies from around 0.08-0.21 cents per KWh but mine's 12.6 so let's use that. That's $4.64. Now consider that I get more useable life out of one made from better parts with less heat floating around. It does pay for itself over time but not much more. A diablotek PHD350 is in the mid 70% range and $22. A seasonic 350W bronze PSU is around $45. Add in room cooling costs and you might make a buck. I'd do it just for fan noise, air temperature, reliability, etc.

Re:The Maths (1)

epyT-R (613989) | about 2 years ago | (#42283077)

a diablotek is also likely to die and take your expensive computer with it.

Re:The Maths (2, Informative)

jamesh (87723) | about 2 years ago | (#42282663)

new efficiency @ load % - old efficiency @ load % = delta%
integrate over time (delta%*cost kw/hr) until result = new unit cost (solve for t)

You're missing the savings on removing that excess heat from your house too (in climates where that is relevant).

In a cold climate where you are heating your house, unless you can get better $/unit heating out of something else, the "waste" energy is heating the house anyway so it doesn't matter much.

In a hot climate where you are cooling your house, every unit of heat that you put into the house has to be removed. Firstly from the computer by making the fans work harder, then from the house itself by making your AC work harder.

Please revise your maths accordingly.

Re:The Maths (1)

gewalker (57809) | about 2 years ago | (#42283135)

If you are in a cold climate and you don't have something cheaper than electric resistance heating you are doing it wrong. I know that in the case of running a heat pump it defaults to resistance heating as a backup mode when it is very cold outside. But you are really paying too much if you do this all the time (and my grandmother's house has resistance heating and she keeps it about 80 degrees)

Re:The Maths (1)

CanadianRealist (1258974) | about 2 years ago | (#42283229)

So living in an apartment is "doing it wrong"?

Most of the apartments I've lived in had electric baseboard heating. For some reason the building owners didn't want to let me install my own gas furnace. Maybe I should ask them if I can drill from the 20th floor down to the ground and a bit more so I can install a heat pump.

Re:The Maths (1)

Kaenneth (82978) | about 2 years ago | (#42283143)

I'm not an electrical engineer, but I don't believe all waste energy is heat, some of it is probably RF energy that's not absorbed before it leaves your building.

However, in my case, switching to higher efficiency power supplies meant I no longer had to run my air conditioner even while there was snow outside. That's a pretty big power savings.

If it's worth squeezing the last 1-2% is a different question.

I'll bet... (4, Funny)

msauve (701917) | about 2 years ago | (#42282231)

we could probably use a computer to figure out the answers to those questions!

Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282239)

If so, you're probaby wasting your money on an "efficient" power supply.

Re:Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282261)

Not in the summer. Anytime your AC has to pump the heat out of the house that your computer has generated, you're wasting money. In the winter, you're better off using natural gas for heat - it's cheaper.

Re:Do you heat your house? (1)

zwarte piet (1023413) | about 2 years ago | (#42282425)

My rental house only has electric heating. Gas comes in bottles here.

Re:Do you heat your house? (1)

larry bagina (561269) | about 2 years ago | (#42282277)

Division of labor. You need to consider if your heating system is more efficient at heating than your power supply is.

Re:Do you heat your house? (4, Interesting)

OneAhead (1495535) | about 2 years ago | (#42282423)

Get your head out of your ass. Most electric heating is done with heat pumps. A heat pump pumps more heat into your house than the electric energy it consumes (that's why it's called that way). Heating by burning something is also more efficient than dissipating electric energy because you're cutting out conversion (see Carnot efficiency) and transportation losses.

And in the summer, if the AC is on, inefficient appliances make you lose double: once by consuming more electricity than they should, and a second time because the AC needs to consume energy to pump the heat out of your house.

Re:Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282481)

And in the summer, if the AC is on...

Hell, I'm on right now!

Re:Do you heat your house? (1)

deniable (76198) | about 2 years ago | (#42282747)

Of course, it's summer here now.

Re:Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282495)

A heat pump pumps more heat into your house than the electric energy it consumes.

Excellent!

Perhaps I could interest you in my perpetual motion machine? One careful owner...

Re:Do you heat your house? (2, Informative)

Anonymous Coward | about 2 years ago | (#42282585)

This is why "software engineer" is a term I will never use willingly. It is an insult to real engineers. Heat pumps do in fact put more heat into their hot side than they consume in work. They take heat from a low temperature resivoir and send it to a high temperature resivoir.

Re:Do you heat your house? (0)

rossdee (243626) | about 2 years ago | (#42283145)

" Heat pumps do in fact put more heat into their hot side than they consume in work. They take heat from a low temperature resivoir and send it to a high temperature resivoir."

So they work well in heating a house as long as its not cold outside. Probably not so good in a real winter..

Re:Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282591)

-1 ignoramus.

Re:Do you heat your house? (5, Insightful)

ShogunTux (1236014) | about 2 years ago | (#42282833)

Perhaps the "pump" part of heat pump completely eluded you, since they do not defy the first law of thermodynamics as you seem to be implying.

Heat pumps work by having a sink source off of which they are pumping the heat from or away from. Most of the ones I know happen to be geothermal, which work because the sink which they are pumping from maintains a constant temperature year long underground. So, during the summer, the heat they can extract from that source would be cooler than the air above ground, but during the winter be hotter. They do this by extracting the heat from the source sink, rather than producing it themselves.

So in that respect, they work much like the fan does within your computer, since the air inside the case is much hotter when running than the air outside of the case. The fan can then displace that heat generated inside rather efficiently by just pushing the hotter air inside the case out, while bringing the cooler air from the room outside in without having to require an equal amount of energy to then power those fans as the equipment running inside of it, thus, like the grandparent, requiring less electric energy to power those fans than what the computer itself uses. If this were not so, then it'd make a lot more sense to completely seal computer cases, as the cooling benefit from the fans wouldn't make up for the amount of dust which they bring into the case during operation.

So the next time you're tempted to call bullshit on a well known physics principle, make sure you double check that you're not making some stupid mistake. Or else you'll end up looking rather foolish again when someone else points out how you don't know what you're talking about.

Re:Do you heat your house? (1)

tragedy (27079) | about 2 years ago | (#42282729)

Can you really qualify heating done with heat pumps as electric heating? My house is heated with hot water from a gas furnace recirculated using an electric pump. By your definition of electric heating, wouldn't that make my house electrically heated? Also, aren't there transportation and conversion losses from burning something for heat just as there are with electric heating?

And in the summer, if the AC is on, inefficient appliances make you lose double: once by consuming more electricity than they should, and a second time because the AC needs to consume energy to pump the heat out of your house.

I'm not sure what method you can possibly imagine for pumping heat out of your house that doesn't consume energy.

Re:Do you heat your house? (0)

Anonymous Coward | about 2 years ago | (#42282741)

Around here, when people say electic heat they almost always mean resistive electric baseboards, which are near 100% efficient. And our electricity is 93% hydroelectric. Gas furnaces send several tens percent of the heat up the chimney. Some lucky people have had their gas furnaces retrofit as a heat pump, but that takes substantially more work if you are starting with electric baseboards.I have been in one house that hydronic radiant floors with a geothermal heat pump, it was glorious, but hard to do as a retrofit. Here, hydronic radiators are just not available at home suppliers, so converting to solar hydronic is difficult.

Re:Do you heat your house? (1)

drainbramage (588291) | about 2 years ago | (#42283023)

I live in (Western) Washington State, heat pumps are rare.
Seems like well less than 10 percent of heating systems.
Oil heat used to be the king here, gas or oil systems converted to gas seem to be the norm now.
Heating is the issue here, not cooling.So, maybe you you can take a break on the attitude, depending on where your head is.
---
Tried googling for percentage of heating system types in use but got nothing useful, kind of like here.

Not an investment (1)

MSTCrow5429 (642744) | about 2 years ago | (#42282267)

An investment is expected to bring a net positive return over time, not bring the expected loss closer to zero.

Re:Not an investment (2)

AK Marc (707885) | about 2 years ago | (#42282607)

That may be for the subset of "financial investment" but more generically:

an investment is something that returns more value than it costs.

By my definition, a car that depreciates is an "investment" because with it you were able to get a job and make more than the car cost, even if the car itself was a loss. The power supply is the same. If you count the added cost of an 80% efficient supply, you may never make back the difference, unless you count the air conditioning savings, and put a price on the externalities of increased electrical demand and such.

But in my case, the small difference was worth it by paying for itself back (including cost of capital, for those who would point that out) within 5 years. But then, I was only looking at the expensive supplies in the first place because I've found that the better supplies lower unidientified lockups, and help eliminate intermittent computer problems. So if you are looking for the cheapest power supply at 250W, and the 80% efficient one is a respectable brand and you find a no-name one for much cheaper, the no-name is the best financial decision, so long as you look at no other factors. The 80% one is an "investment" in reliable computing.

Re:Not an investment (3, Insightful)

Darinbob (1142669) | about 2 years ago | (#42282783)

If you're only factoring just the electricity bill as a factor. But there are also environmental reasons maybe and it's harder to put an unemotional price on that. This is sort of like the people who claim hybrid electric cars are a waste of money since they're only looking at the wallet and not the bigger picture. It's more than just saving a little electricity as well, there is also the slight increase in customer demand, which slightly increases the market forces towards creating more efficient products in general.

Bought one (1)

miknix (1047580) | about 2 years ago | (#42282273)

Bought one Antec Earthwatts long time ago. The PSU was not much more expensive than the others (good brands) so the savings are obvious. Still, the PSU is very quiet which is the main reason why I bought it.

Re:Bought one (0)

Anonymous Coward | about 2 years ago | (#42282427)

Both my systems (workstation, NAS) are running Antec Earthwatts PSUs for that reason. They're ridiculously quiet, and so far, they've been rock solid in terms of reliability.

TBH, I really don't give a damn about power/conversion efficiency - I'm running two systems 24x7, with little impact on my power bill. If I was concerned about saving money there, a computer PSU would be the last place I'd look for savings. Now my air conditioning... Ahhh, there's the massive money waster.

Cooler (2, Informative)

Anonymous Coward | about 2 years ago | (#42282307)

One advantage of a more efficient PSU is that it runs cooler. This is nice at least if you are going for a silent system, as less fans are then required.

"FEWER" FANS, COCKNOZZLE. USE LANGUAGE CORRECTLY (1)

Subject Line Troll (581198) | about 2 years ago | (#42282381)


 

Re: "FEWER" FANS, COCKNOZZLE. USE LANGUAGE CORRECT (0)

Anonymous Coward | about 2 years ago | (#42282671)

This is nice at least if you are going for a silent system, as fewer fans, cocknozzle.

CIA Head: We Will Spy On Americans Through Electri (-1)

Anonymous Coward | about 2 years ago | (#42282319)

CIA Head: We Will Spy On Americans Through Electrical Appliances

Global information surveillance grid being constructed; willing Americans embrace gadgets used to spy on them

Steve Watson | Prisonplanet.com | March 16, 2012

http://www.prisonplanet.com/cia-head-we-will-spy-on-americans-through-electrical-appliances.html [prisonplanet.com]

"CIA director David Petraeus has said that the rise of new "smart" gadgets means that Americans are effectively bugging their own homes, saving US spy agencies a job when it identifies any "persons of interest".

Speaking at a summit for In-Q-Tel, the CIAâ(TM)s technology investment operation, Petraeus made the comments when discussing new technologies which aim to add processors and web connections to previously âdumbâ(TM) home appliances such as fridges, ovens and lighting systems.

Wired reports the details via its Danger Room Blog[1]:

"âTransformationalâ(TM) is an overused word, but I do believe it properly applies to these technologies," Petraeus enthused, "particularly to their effect on clandestine tradecraft."

"Items of interest will be located, identified, monitored, and remotely controlled through technologies such as radio-frequency identification, sensor networks, tiny embedded servers, and energy harvesters - all connected to the next-generation internet using abundant, low-cost, and high-power computing," Petraeus said.

"the latter now going to cloud computing, in many areas greater and greater supercomputing, and, ultimately, heading to quantum computing." the CIA head added.

Petraeus also stated that such devices within the home "change our notions of secrecy".

Petraeusâ(TM) comments come in the same week that one of the biggest microchip companies in the world, ARM, unveiled new processors that are designed to give practically every household appliance an internet connection[2], in order that they can be remote controlled and operate in tandem with applications.

ARM describes the concept as an "internet of things".

Where will all the information from such devices be sent and analyzed? It can be no coincidence that the NSA is currently building a monolithic heavily fortified $2 billion facility[3] deep in the Utah desert and surrounded by mountains. The facility is set to go fully live in September 2013.

"The Utah data center is the centerpiece of the Global Information Grid, a military project that will handle yottabytes of data, an amount so huge that there is no other data unit after it." reports Gizmodo.

"This center-with every listening post, spy satellite and NSA datacenter connected to it, will make the NSA the most powerful spy agency in the world."

Wired reports[4] that the incoming data is being mined by plugging into telecommunications companiesâ(TM) switches, essentially the same method the NSA infamously uses for warrantless wiretapping of domestic communications[5], as exposed six years ago.

Former intelligence analyst turned best selling author James Bamford, has penned a lengthy piece[6] on the NSA facility and warns "It is, in some measure, the realization of the âtotal information awarenessâ(TM) program created during the first term of the Bush administration-an effort that was killed by Congress in 2003 after it caused an outcry over its potential for invading Americansâ(TM) privacy."

----------------------

Steve Watson is the London based writer and editor for Alex Jonesâ(TM) Infowars.net[7], and Prisonplanet.com[8]. He has a Masters Degree in International Relations from the School of Politics at The University of Nottingham in England.

© 2012 PrisonPlanet.com is a Free Speech Systems, LLC company. All rights reserved.

[1] http://www.wired.com/dangerroom/2012/03/petraeus-tv-remote/ [wired.com]
[2] http://www.bbc.co.uk/news/technology-17345934 [bbc.co.uk]
[3] http://gizmodo.com/5893869/this-is-the-most-powerful-spy-center-in-the-world [gizmodo.com]
[4] http://www.wired.com/threatlevel/2012/03/ff_nsadatacenter/all/1 [wired.com]
[5] http://en.wikipedia.org/wiki/NSA_warrantless_surveillance_controversy [wikipedia.org]
[6] http://www.wired.com/threatlevel/2012/03/ff_nsadatacenter/ [wired.com]
[7] http://infowars.net/ [infowars.net]
[8] http://prisonplanet.com/ [prisonplanet.com]

Heating and Cooling (0)

Anonymous Coward | about 2 years ago | (#42282323)

Have electric heat? No gain.

Have air conditioning? Big gain.

Want a quite computer? Some gain.

Turn down the screen brightness (2)

Circlotron (764156) | about 2 years ago | (#42282327)

If you reduce the brightness of an LCD screen backlight it will also lower power consumption. Mine uses 40 watts full brightness and 20 watts dark. So if you shave off 10 watts it may nearly equal the savings of a good psu but for no outlay.

Re:Turn down the screen brightness (0)

Anonymous Coward | about 2 years ago | (#42282835)

I tried reading the last comment, but I couldn't make out the letters over the dark background......

Re:Turn down the screen brightness (1)

Circlotron (764156) | about 2 years ago | (#42283201)

I tried reading the last comment, but I couldn't make out the letters over the dark background......

You need to sit in a darkened room that is "blacker than black" like analogue video sync pulses. Then you don't even need to turn the screen on to use it. Just think how much *that* would save.

Small price difference (1)

OneAhead (1495535) | about 2 years ago | (#42282339)

Have you looked at the price difference between different efficiencies for the same wattage? They're usually minimal. So might as well vote with your wallet and go for the highest-efficiency one. There's no telling how electricity prices will evolve over time...

The power maths... (1)

Fishead (658061) | about 2 years ago | (#42282361)

To make the maths easier, lets assume you can improve your efficiency by 25% (that's huge) and assume you're loading it to 400 watts, (also huge) and assume you run it 8 hours a day, 5 days a week with 2 weeks off a year (running at full capacity).

That's 100 watts of savings, 2000 hours a year... 0.1kw X 2000 = 200kWh per year.

I pay about $0.10/kWh

You could save up to $20/year.

Reality? You'd probably see a lot less savings then that.

Re:The power maths... (1)

blueg3 (192743) | about 2 years ago | (#42282497)

Okay, "up to" only applies if you are computing using reasonable maximums, which you aren't. $20/year is a reasonable estimate, but not "up to".

25% efficiency improvement is pretty big. 400 W is a large load for some machines, but isn't that huge a load. $0.10/kWh is actually substantially below the US average of $0.12/kWh.

The biggest variable factor here, though, is computer uptime. Hugely variable. My home PC probably sees 500-800 hr/yr use. My work PC probably sees your estimate of 2000 hr/yr. My HTPC is on all the time, which would be ~8700 hr/yr if it didn't occasionally go to sleep. Many of my coworkers' work computers are on all the time and don't go to sleep -- which is really about 8700 hr/yr.

So that's a factor of 10 difference between one reasonable usage scenario and another common but slightly less reasonable scenario. That makes a big difference.

Re:The power maths... (0)

Anonymous Coward | about 2 years ago | (#42282603)

But if you draw 200W for 24h per day 365 days of the year and only get a 10% saving you would save $17.

Given the benefits of a quieter machine with a potentially longer lasting PSU (presumably better made than the cheaper less efficient ones) then shelling out an extra $20 may save you a few times that over the course of 5 years of the PSU's lifetime.

Moonpie (-1)

Anonymous Coward | about 2 years ago | (#42282369)

Memorable quotes for
Looker (1981)
http://www.imdb.com/title/tt0082677/quotes [imdb.com]

"John Reston: Television can control public opinion more effectively than armies of secret police, because television is entirely voluntary. The American government forces our children to attend school, but nobody forces them to watch T.V. Americans of all ages *submit* to television. Television is the American ideal. Persuasion without coercion. Nobody makes us watch. Who could have predicted that a *free* people would voluntarily spend one fifth of their lives sitting in front of a *box* with pictures? Fifteen years sitting in prison is punishment. But 15 years sitting in front of a television set is entertainment. And the average American now spends more than one and a half years of his life just watching television commercials. Fifty minutes, every day of his life, watching commercials. Now, that's power."

##

"The United States has it's own propaganda, but it's very effective because people don't realize that it's propaganda. And it's subtle, but it's actually a much stronger propaganda machine than the Nazis had but it's funded in a different way. With the Nazis it was funded by the government, but in the United States, it's funded by corporations and corporations they only want things to happen that will make people want to buy stuff. So whatever that is, then that is considered okay and good, but that doesn't necessarily mean it really serves people's thinking - it can stupify and make not very good things happen."
- Crispin Glover: http://www.imdb.com/name/nm0000417/bio [imdb.com]

##

"It's only logical to assume that conspiracies are everywhere, because that's what people do. They conspire. If you can't get the message, get the man." - Mel Gibson (from an interview)

##

"We'll know our disinformation program is complete when everything the American public believes is false." - William Casey, CIA Director

##

"The real reason for the official secrecy, in most instances, is not to keep the opposition (the CIA's euphemistic term for the enemy) from knowing what is going on; the enemy usually does know. The basic reason for governmental secrecy is to keep you, the American public, from knowing - for you, too, are considered the opposition, or enemy - so that you cannot interfere. When the public does not know what the government or the CIA is doing, it cannot voice its approval or disapproval of their actions. In fact, they can even lie to your about what they are doing or have done, and you will not know it. As for the second advantage, despite frequent suggestion that the CIA is a rogue elephant, the truth is that the agency functions at the direction of and in response to the office of the president. All of its major clandestine operations are carried out with the direct approval of or on direct orders from the White House. The CIA is a secret tool of the president - every president. And every president since Truman has lied to the American people in order to protect the agency. When lies have failed, it has been the duty of the CIA to take the blame for the president, thus protecting him. This is known in the business as "plausible denial." The CIA, functioning as a secret instrument of the U.S. government and the presidency, has long misused and abused history and continues to do so."
- Victor Marchetti, Propaganda and Disinformation: How the CIA Manufactures History

##

George Carlin:

"The real owners are the big wealthy business interests that control things and make all the important decisions. Forget the politicians, they're an irrelevancy. The politicians are put there to give you the idea that you have freedom of choice. You don't. You have no choice. You have owners. They own you. They own everything. They own all the important land. They own and control the corporations. They've long since bought and paid for the Senate, the Congress, the statehouses, the city halls. They've got the judges in their back pockets. And they own all the big media companies, so that they control just about all of the news and information you hear. They've got you by the balls. They spend billions of dollars every year lobbying lobbying to get what they want. Well, we know what they want; they want more for themselves and less for everybody else.

But I'll tell you what they don't want. They don't want a population of citizens capable of critical thinking. They don't want well-informed, well-educated people capable of critical thinking. They're not interested in that. That doesn't help them. That's against their interests. They don't want people who are smart enough to sit around the kitchen table and figure out how badly they're getting fucked by a system that threw them overboard 30 fucking years ago.

You know what they want? Obedient workers people who are just smart enough to run the machines and do the paperwork but just dumb enough to passively accept all these increasingly shittier jobs with the lower pay, the longer hours, reduced benefits, the end of overtime and the vanishing pension that disappears the minute you go to collect it. And, now, they're coming for your Social Security. They want your fucking retirement money. They want it back, so they can give it to their criminal friends on Wall Street. And you know something? They'll get it. They'll get it all, sooner or later, because they own this fucking place. It's a big club, and you ain't in it. You and I are not in the big club.

This country is finished."

##

[1967] Jim Garrison Interview "In a very real and terrifying sense, our Government is the CIA and the Pentagon, with Congress reduced to a debating society. Of course, you can't spot this trend to fascism by casually looking around. You can't look for such familiar signs as the swastika, because they won't be there. We won't build Dachaus and Auschwitzes; the clever manipulation of the mass media is creating a concentration camp of the mind that promises to be far more effective in keeping the populace in line. We're not going to wake up one morning and suddenly find ourselves in gray uniforms goose-stepping off to work. But this isn't the test. The test is: What happens to the individual who dissents? In Nazi Germany, he was physically destroyed; here, the process is more subtle, but the end results can be the same. I've learned enough about the machinations of the CIA in the past year to know that this is no longer the dreamworld America I once believed in. The imperatives of the population explosion, which almost inevitably will lessen our belief in the sanctity of the individual human life, combined with the awesome power of the CIA and the defense establishment, seem destined to seal the fate of the America I knew as a child and bring us into a new Orwellian world where the citizen exists for the state and where raw power justifies any and every immoral act. I've always had a kind of knee-jerk trust in my Government's basic integrity, whatever political blunders it may make. But I've come to realize that in Washington, deceiving and manipulating the public are viewed by some as the natural prerogatives of office. Huey Long once said, "Fascism will come to America in the name of anti-fascism." I'm afraid, based on my own experience, that fascism will come to America in the name of national security."

Quieter and cooler (3, Interesting)

Manfre (631065) | about 2 years ago | (#42282377)

Higher efficiency means less waste heat coming from the power supply, so its fan can run quieter.

for continuous service machines; ONE BILLING CYCLE (1)

Narcocide (102829) | about 2 years ago | (#42282379)

Antec 650W "green" power supply.

Upgraded to this from a 500W older model Antec power supply for my primary desktop, which is *never* powered off, except during hardware upgrades like replacing the power supply. My local electrical company bills every other month. The power supply cost me i believe around 80-90$ after tax and it paid for itself within one billing cycle.

Waste energy is converted to heat (2, Insightful)

SplatMan_DK (1035528) | about 2 years ago | (#42282417)

Since the waste energy is converted to heat (which may increase the noise or temperature of the machine) it may well be worth the extra cash anyway.

Saving a few bucks on electricity is hardly the only reason to buy a more efficient power supply.

- Jesper

Re:Waste energy is converted to heat (0)

Anonymous Coward | about 2 years ago | (#42282829)

I buy an inefficient power supply because I live in a cold climate.

that isn't the logo to be looking at (1)

sdnoob (917382) | about 2 years ago | (#42282433)

don't choose a cheap piece of shit just because it claims a higher '80 plus' certification level than a quality, name brand unit from a reputable company that might cost twice as much.

Re:that isn't the logo to be looking at (1)

bill_mcgonigle (4333) | about 2 years ago | (#42282933)


don't choose a cheap piece of shit just because it claims a higher '80 plus' certification level than a quality, name brand unit from a reputable company that might cost twice as much.

yeah, this hits home. I just replaced my second failed Rosewill 80+ today (5-star reviews...). Visible build quality on the first two were great, but obviously the guts aren't so good. I'm gonna open it and look for mushroomed caps.

The third one, my only spare-on-hand is of such poor build quality that the metal conductors in the Molex connectors aren't even locked in place. One went in crooked and pushed the other connector in the other-gender Molex out a bit. That took the whole chain out and took an hour to trace...

so... Slash-hive : does Antec still use good caps? I've got an ASRock in that machine for good Japanese caps; might as well pair a usable power supply.

Re:that isn't the logo to be looking at (1)

Mashiki (184564) | about 2 years ago | (#42283001)

Yeah Antec is good generally, most of their stuff is made by seasonic. So is OCZ(generally), mushkin, and a few others. I'd recommend looking through here. [hardwaresecrets.com] And see who is making what it can change sometimes between revisions. And generally the reviews are quite good. And each PSU has a teardown, including what's being jammed inside the guts. So you have a fairly good idea of what components are being used.

Quality, noise, heat... (1)

evilviper (135110) | about 2 years ago | (#42282447)

These days, 80plus PSUs are very cheap. The only things cheaper are unreliable JUNK PSUs which won't last a year. Also, because of the legal terms of using the 80plus trademark, manufacturers seem to not inflate the wattage ratings on 80plus PSUs, while you can easily find $15 "2000watt" junk PSUs.

And besides all that, I'd pay the 80plus premium just for the heat/noise reduction. Combine with a WD "Green" hard drive (or SSD), low-power CPU, and a couple low-noise fans, and you've got a very low heat and very, very quiet system.

Let me guess what the summary says... (0)

cyberjock1980 (1131059) | about 2 years ago | (#42282455)

I haven't read the article yet. I'm about to .. but let me guess what the whole story summed up will say:

"You need to look at cost for the unit and the expected lifespan of the device as well as the expected load and and cost of the electricity to determine if you can save any money by purchasing a more efficient power supply."

I've had some machines that it makes sense to upgrade, and others that it doesn't.

Of course, if you are all about saving the planet then you'll buy the most power efficient power supply on the market regardless of price because you think its saving the planet. Of course, it may not be doing such thing since you expended more resource materials to manufacture the power supply, etc. Not to mention it might cost you more in the long run than the less expensive less efficient power supplies.

I care for stability more (1)

BLToday (1777712) | about 2 years ago | (#42282507)

There's nothing more frustrating that having a flaky PSU. It can masquerade as any other computer issues.

UPS?? (0)

Anonymous Coward | about 2 years ago | (#42282535)

If you have a UPS, high efficiency PFC power supplies are a must.

If you don't, then just do the math. 100W wasted * $0.10/kWh * 365days * 10h/day = $36.50/yr. So if you get a good power supply, with a 5 year warranty, that saves you about $100-$150 minimum in electricity alone and that is if you have the PC on average 10h/day. For people that have it on 24/7 like a server, you are looking at $250-$400 savings, never mind on replacing any crappy power supplies that last a year and die on you, possibly taking the system with it.

Even if you only save 25W in efficiency on a 24/7 system, that works out to $110+tax saved over 5 years. It pays for itself much quicker than that!

It is a no-brainer to go with high efficiency, long warranty power supplies.

Save more by buying small (3, Informative)

anyaristow (1448609) | about 2 years ago | (#42282545)

A PSU has a power efficiency curve that looks like this [anandtech.com] . That article also explains what I'm about to summarize:

Pick a PSU that is no more powerful than you need, to keep your system in the middle of that curve, for maximum efficiency. 100% margin is more than plenty, so if your components will use 250W max, you don't need a 900W PSU. Look for something in the 500 range, or even less if you pick a good-quality PSU.

You probably won't be able to make a cost argument for maximizing efficiency, but you can build a quieter system focusing on efficiency, and it's quite satisfying obsessing over something different.

Quality, heat, noise, etc. (0)

Anonymous Coward | about 2 years ago | (#42282549)

The better 80+ units are typically made of better components (Japanese caps, for instance) and are typically more reliable and have better voltage regulation. They convert less current to heat, reducing net heat load and ultimately cooling noise.

I'll buy high efficiency units even if the net cost is higher, which it probably is in my case. It's nice to know a heavily used 80+ unit will save its own cost in power in a few years, but cost isn't my highest priority.

BTW, Seasonic X series are outstanding power supplies.

Match Your Power supply to System Power Reqs (1)

Proudrooster (580120) | about 2 years ago | (#42282551)

A while ago I purchased an EZ-Watt meter so see how Much power that my system was consuming. I found that my system at max CPU and GPU load consumes about 350 W of power. So my question is why would I buy a green 800 Watt power supply when my system only needs 300 W? It seems that it would be best to match the power supply to the system in order to maximize savings since the efficiency of the power supply is calculated at its maximum rating. How much power doesn't 800 Watt power supply consume when the system is using only hundred to 200-300 W? It would be interesting to connect it to a wattmeter and find the answers. I suspect that a standard power supply matched to the system power requirements would result in a larger power/money savings then buying an oversized high-efficiency power supply.

Re:Match Your Power supply to System Power Reqs (1)

tragedy (27079) | about 2 years ago | (#42282911)

It depends a lot on whether "about 350 W" is a maximum or an average and even more on what you've been doing with your computer while you measure. Measuring draw like that is a good idea, but it doesn't tell you everything. There very well may be usage patterns for components in your system that some software may cause that are higher than your normal usage. If you start using your computer a different way (say by running a demanding game which uses your CPU, hard drives, optical drives and gpu hard all at the same moment) then it may abruptly shut down or blow up its power supply if you based your power supply choice on typical draw.

The proper way to do it is always to find out the documented maximum draw of each component in the computer and add them all together. Then, the power supply you get should be at least 20% higher than that. Power supply ratings, especially in the certified ones being discussed in this article, have been improving, but the conventional wisdom is that the wattage rating of a power supply represents a momentary peak the power supply may be able to achieve, but that if you run even close to it for any length of time, the power supply will burn out.

Also, as mentioned in the summary, these power supplies are rated for efficiency at varying levels of load, so a 400 Watt regular power supply running at 350 watts should use more power than a high-efficiency 4000 Watt power supply running at 350 watts.

Re:Match Your Power supply to System Power Reqs (1)

DigiShaman (671371) | about 2 years ago | (#42282953)

So my question is why would I buy a green 800 Watt power supply when my system only needs 300 W?

Components degrade with time. Specifically with regards to electrolytic capacitors. As the PSU ages, the ability for them to run a peak ratings diminish. At best, you get excessive DC ripple that puts a strain on your motherboard components. *Always* purchase a PSU that at least rated for 30% more power than what you need!

How much power doesn't 800 Watt power supply consume when the system is using only hundred to 200-300 W?

If it's rated for 80% efficiency for AC/DC -conversion-. It will only convert whatever the load is to 20% heat. So if you're only using 8 watts DC, that's 10 watts being pulled from AC. If it's 80 watts DC, that's 100 watts AC.

Re:Match Your Power supply to System Power Reqs (3, Informative)

MtHuurne (602934) | about 2 years ago | (#42283177)

If you look at efficiency graphs, you'll see that power supplies are typically the most efficient under moderate load: at low and high load the efficiency drops. A typical desktop or home server is idle most of the time, so idle efficiency will have a big impact on the total efficiency. If you over-dimension your power supply, your idle load might be 10% or less of the max rating, which is far from the optimum of the efficiency curve.

I'd recommend getting a power supply that can deliver a bit more than what you need, for example 450 W if you think you need 350 W max. A bit of margin is useful since you might not have found the actual worst case or you might want to add components later. Also it avoids poor efficiency at the high side of the curve when the system is under load.

No. (1)

complete loony (663508) | about 2 years ago | (#42282557)

Betteridge strikes again.

extra heat could be a bigger problem (0)

Anonymous Coward | about 2 years ago | (#42282571)

I don't know about the investment aspect, to me the more pressing issue is that the inefficient part of the power is converted into heat that now needs to be removed out of your case by blowing fans. So if you are building a rig where you intend to use a lot of high end components, you will need high power supply, and if it is inefficient it may significantly increase the heating issues inside your build and cause instabilities and shorten the life span of your components. And/or a loud noise.

Better capacitors? (1)

The Grim Reefer (1162755) | about 2 years ago | (#42282597)

I've often wondered if the more efficient PSUs used better capacitors. If the extra cost needs to be offset by longer usage, will the capacitors hold up better/longer? I would guess that if the PSU runs cooler it should be an improvement in the capacitors useful life too. But the total output from a PSU decreases over time. I've used this PSU calculator [outervision.com] over the years. In footnote 4 they mention the decreased output over time.

It's not just the power (2)

AdamHaun (43173) | about 2 years ago | (#42282643)

Noise is also a factor. High-efficiency supplies have fans that run more slowly under load, or not at all. If you're building a quiet system, this is a big deal.

Note that the peak efficiency is usually at ~50% load, so be sure to size your power supply appropriately for best results. Newegg has a calculator [newegg.com] to help with this.

Choose a lower power PSU if you can (1)

aNonnyMouseCowered (2693969) | about 2 years ago | (#42282673)

Unless you really need it, then choose something more modest than a honking 1000W PSU. Not a frag-fracking gamer? A 90W DC PSU should have enough juice for your 65W CPU. As PSU efficiency is measured in percentage, even a 50% inefficient 90W PSU will beat a 95% efficient 1000W PSU.

Re:Choose a lower power PSU if you can (1)

BLKMGK (34057) | about 2 years ago | (#42282861)

My experience is that nearly everyone overestimates their PSU needs and it becomes a game of "who's is bigger?". This is a stupid way to pick hardware. My desktop runs a 650, my ESX server with 24+ bays runs an 850. If I had a way better video card in the desktop I might move to a 750 and I wouldn't run dual cards.

My HTPC with ion chipsets use 9-16 watts at the wall at 100% usage.

Check the reviews (1)

pokoteng (2729771) | about 2 years ago | (#42282723)

As mentioned, efficiency of PSU changes over variety of conditions (load being most significant), so it's good to check reviews that do proper measurements to get the one that has good efficiency all across the range. Unlike posts above, it doesn't always fall at 50% mark. That said, good PSUs often sport high efficiency for a reason; they're made well. It'll serve you well to get a really high quality PSU if anything so it doesn't blow up on you, possibly losing all sorts of other parts in the computer, which would cost a lot more than just larger electricity bill.

not worth buying new psu for ..but (2)

atarione (601740) | about 2 years ago | (#42282773)

so it probably for 99% of the people won't make sense to upgrade a power supply just for efficiency

but if for some reason you need a new power-supply anyways finding a good quality (80+ gold ..etc) unit on sale is totally reasonable.... at this point most units worth trusting the rest of your gear to are probably 80+ anyways.

in my own case i had been using a 80+ power-supply that wasn't modular and cables where a hassle to manage ... i wanted a modular power-supply and also have no intention of risking a $200 processor and $300~ video card etc to a generic / shoddy power-supply so i found the Seasonic X750 (80+ Gold ) on sale for $100~ (which if you look at newegg is cheaper than any 700-800watt fully modular power supplies currently.

since i wanted/needed fully modular 750~ish watt power-supply finding the X750 for $99 made sense as it was cheapest meeting those requirements.... the fact is it 80+ is just bonus ... seasonic's 5year warr and generally pretty good reputation for quality power supplies drove the choice more than the 80+ gold.

It's not just about effeciency... (1)

BLKMGK (34057) | about 2 years ago | (#42282803)

The design choices that manufacturers make in order to meet these levels of effeciency have other impacts. Active power management, cooling fans that only run when needed, and higher quality components are all good reasons to consider a higher effeciency rated PSU. My computers often run 24x7 for years on end so I tend to choose decent PSU.

Also, just as a data point, I have a 4U box running a Xeon, 32gig of RAM, many cooling fans, 3x SAS cards, an SSD, and at least 20x HDD. It has a gold rated PSU listed as 850watts. Oh yeah, integrated onboard video. Usage at the plug? With all drives spinning actively it uses right at 200watts! Less when unRAID spins drives down, none of the drives are "green". The number surprised me!

Discriminating the junk "factor" (1)

Meeni (1815694) | about 2 years ago | (#42282811)

Most PSU that do not sport the 80+ badge are outright junk that does not respect environmental and security norms in the first place, and will blow up in a variety of creative ways if you were to draw half of what is written as max wattage on the sticker. The 80+ badge weeds out most of the crap (not all though).

It's not all about efficiency (1)

EmagGeek (574360) | about 2 years ago | (#42282931)

So there are a lot of factors that influence the production cost of a power supply. Some of the newer quasi-resonant and PFC-Forward designs are very good at eliminating switching losses, and are relatively cheap until you get to the switch and transformer, which are the critical loss pieces in a given switching supply design. It is justified that a 90% efficient supply costs more than an 80% efficient supply, because the component and design costs both go up.

But, whether or not you choose one can be influenced by many factors that don't necessarily have anything to do with efficiency.

First, a high-efficiency supply is going to throw off less waste heat. Lower temperatures mean components, especially liquid electrolyte capacitors, last longer.

Second, reliability. The #1 cause of power supply failure is the fan. A high-E supply can get away without a fan up to maybe 500W in a standard ATX form factor. So, your lower-power HTPC or workstation can benefit from being less noisy, and never having to worry about a fan failing and causing catastrophic failure.

Third, finally, overall power draw. If you're running a server 24/7 the power savings add up over time. If power is expensive, and your machine with its cheap-ass 60% efficient supply is drawing 500W from the wall, increasing your P/S efficiency to 90% will reduce your power consumption to 333W, saving 120kWh/month, which for me is about $15/month. That pays for the higher efficiency inside of a year.

I think will make sense to buy the 80-Plus Gold supply for $150 if you have a high-draw machine with a cheap-ass 60% efficient gray-box supply - every time.

GlobalWarming@Home (1)

Kaenneth (82978) | about 2 years ago | (#42283187)

I've been wanting to start a project; 'GlobalWarming@Home', with client software for people who want to contribute to the global warming effort.

All it would do is run your CPU/GPU full tilt, using as much power as possible to 'contribute' to global warming.

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