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Power Supply Torture Test
An anonymous reader writes "With the latest batch of power hungry graphics cards, the PSU in your computer is more important than ever. If you're looking for a new power supply, check out this group test. They've tested 19 PSUs - some good, some bad and some downright explosive!"
If you ask me (and i think you did) the power rating on power supplys useless. I have seen 300W power supplies (good ones) with better power output then cheap 400W.
Its the same scam the PMPO ratings on speakers.
Cruise TT
In soviet russia power supply torture tests you
Maybe the guys at Trusted Reviews don't use the recommended Power Supply of it has been /.ed
http://www.michel.eti.br
wonder what their power supply rating was? =\
sig: Playfully doing something difficult, whether useful or not
Mirrordot link to Trusted Reviews power supply review
500GB of disk, 5TB of transfer, $5.95/mo
They used a good slashdotting to test thier power supplies. Needless to say.....all failed and went up in a wave of smoke and ashes.
>>>>>> Chewie, take the professor in the back and plug him into the hyperdrive.
http://mirrordot.com/stories/1a1ed7983abc245725eb
Clicky
Hm, what funny looking headers:
HTTP/1.1 200 OK
Connection: close
Date: Tue, 08 Feb 2005 13:41:42 GMT
Server: Microsoft-IIS/6.0
MicrosoftOfficeWebServer: 5.0_Pub
X-Powered-By: ASP.NET
X-AspNet-Version: 1.1.4322
Cache-Control: public, max-age=79911
Expires: Wed, 09 Feb 2005 11:53:34 GMT
Last-Modified: Tue, 08 Feb 2005 13:40:14 GMT
Content-Type: text/html; charset=utf-8
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(that 'MicrosoftOfficeWebServer')
It's working again, so no worries ;-)
I always stress the importance of getting a good power supply when I give advice for building PCs, but it seems like something people are largely willing to gloss over, and just go for some cheap no-name with high wattage. It's nice to see a review for these, finally...
But, of the companies on here, I've never even [i]heard[/i] of Tagan, and it seems a bit sketchy that Tagan wins best honors in their review... which was conducted in Tagan's lab.
Furthermore, why aren't Sparkle or Antec power supplies tested? Along with Enermax, they're widely regarded as some of the best around.
noise measurements. A l33t PSU is no good if it sets up a howling gale in my room.
In college, I was the guy to go to if you had a computer problem. One night, one of the football players comes knocking on my door, "Hey Mark, my computer's acting weird, can you come look at it?" I agreed and we walked down the hall to his room. Strangely, the machine was off so I reached my hand out and turned it on. I jumped back at the sound of a loud pop and the sight of flames and smoke coming out of the back of the power supply. Immediately, I reached for the cord and pulled the plug.
:-)
"So can you fix it," he asks in all seriousness. I just looked at him in total disbelief and said, "Man, your computer was just on fire. No, I can't fix it."
He was really good at football though!
Mark A. McBride -- OmniNerd.com
That page is annoying, it keeps jumping up and down while I'm trying to read it, because of that stupid javascript ad.
It's kinda silly anyway, the article's premise is that they got access to this $20,000 power supply testing equipment... A set of simple $10-$20 high wattage load resistors would have worked just as well.
A $1000 scope might help if you want to catch a load dump overshoot, startup transient, or ripple, but it looks like they aren't even concerned with such important specs of a power supply, specs that could burn our your system.
Anyway, some testing is better than no testing, which seems to be the norm for computer power supplies, so I am thankful that someone with access did these tests, but it would have been more useful if they had tested more than simply steady state load.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
Anyone have a PSU review summary that includes equipment available in the US?
Come on, you don't need $20000 test equipment to push a tiny little power supply to the edge of its existance. The first paragraph looks more like a marketing scam.
:-)
A nice old 3 inch nail bent up and jammed into the plugs for a few seconds should sort the good supplies from the bad
Probably power-failure.
I owned a Computer Store for 6 years that specialized in hardware service... We would refer to computers that had popped power supplys or "burnt" motherboards as "Home Cooking".
Then, I found in the summary that the prices are in Sterling. Thanks for telling us that this is country-specific.
I always stress the importance of getting a good power supply when I give advice for building PCs....
Personally I'm happy if I can teach users to remember to switch the powersupply from 110 to 220 volts when recieving computers from bought in the USA before plugging them into a 220v power outlet. I still have trouble not laughing out loud every time one of those ebay jockeys shows up with a PC/MAC that has a burned out powersupply. It must be really frustrating to buy a PC/MAC for a shitload of money and then damage or completely ruin it because you forgot to flip one little red switch.
Only to idiots, are orders laws.
-- Henning von Tresckow
Was at a CS "flea market" show in MA, where there are a lot of people selling their wares in a convention center.
This one women tried to convice me that the 400 Watt PSUs were no longer sufficient to run your standard setup, and that you needed the bigger 500 Watt one that she just happened to be selling, for 230 $.
I of course told her to go take a hike.
A bit off-topic, but then the article was slashdotted anyway. I had hell with one of my power units, couldn't figure out why my computer components were failing so rapidly, until a post in Microsoft help and support forums sent me on the right track.
But I'm a bit ambivalent about choosing the word "torture" here, in a jocular or mock serious way. I don't think it's really appropriate to have the term become diluted down to mean anything else than the really worst things that humans can do to each other. Some words should be ringfenced and not put into common usage.
Maybe its just me, but isn't it kind of symptomatic to the overall reaction to atrocities like Guantanamo Bay and Abu Ghraib to misuse the word tortture. It's like it loses its impact. I doubt they editors would have posted something titled "Power Supply Holocaust!" for instance. I think "torture" should be treated like "holocaust", with kid gloves. Otherwise, the language we speak, and therefore think in becomes almost ammoral.
Meine Schwester ist sehr, sehr reizvoll - Nietzsche
Costs a fair bit, weighs more than a house brick and could probably power the rest of the street, but I reckon I need it. When video cards need 1 or 2 molex connectors you know they're sucking up a healthy whack of juice, and I'm running 3 hard drives, 2 DVD burners and about 4 external USB hubs with all kinds of junk plugged in (including 2 external 2.5" drives and 3 external 3.5, although the latter have their own power)
I did that online test where you put in the hardware and it calculates your PSU requirements. Mine said 'portable nuclear power station', but the 550W Antec was all I could find.
Anyone know if card manufacturers are planning slower, low-power modes? I like the way the Athlon 64 winds itself back when not under load, but the fan in my 6800GT runs full tilt despite the fact I use 3d features maybe once a fortnight. (Sure, I wish I could use it more, but work before pleasure and all that.)
Hal Spacejock: Science Fiction with Nuts
My last desktop had to be built twice. Once with a good motherboard, good ram, good processor and Cheap case, the second time with a much better enclosure.
If that case and PS is $45, just HOW MUCH money do you think they're devoting to clean power?
On a more positive note, the new system is dam-near silent as the better case had a large slow moving variable speed fan controlled by the better PS.
"Draco dormiens nunquam titillandus."
The test equipment consisted of two Fast Auto FA-828ATE PSU load testers as well as some additional equipment that was used with power supplies that featured two 12V rails. The PSU load testers were only able to place a load on one of the 12V rails and thus some extra equipment was needed to properly test the latest generation of power supplies.
As we only had two days at the test facility in Germany, we had to limit the amount of tests run. Each PSU was tested at 25, 50, 75 and 100 per cent load on the 12V rail(s), with the 5V and 3.3V rails making up for the additional drain. Those who know something about power supplies, might wonder why we did it this way but the explanation is quite simple. All modern computers put a much heavier load on the 12V rail than the 5 or 3.3V, so this is the most important part to test. However, if you have an older (Pentium III or an early Athlon system) these test results are not going to be quite accurate. This is because older computers relies more on the 5V rail, but as they have much lower power requirements than current machines, all of the power supplies on test should in reality work just fine.
Several changes have recently been made to the ATX PSU specification and some of them are fairly easy to spot, either on the packaging itself or by looking at the connectors. Some of the other changes aren't that obvious, so we are going to list the most important ones.
Dual 12V rails are one of the recent additions and the main reason behind this change is to protect users PCs. With increasing power requirements the amps on the 12V rail have constantly increased, and if this had continued unchecked a PSU failure could potentially result in a fatal accident. With the new design this risk has been greatly reduced and we should see a transition to dual or even quad 12V rails on all high-rated PC power supplies this year.
One other change that is good news for your wallet is that all new power supplies must have a minimum efficiency of 70 per cent at normal load (around 50 per cent load and upwards). It should also be no lower than 60 per cent at light loads (around 20 per cent load or below).
As we'll demonstrate in our tests, the rating on the PSU has nothing to do with how much power your PSU actually draws from the wall socket. What is of more significance is its efficiency. The difference between how much power a PSU draws and how much it actually delivers to the motherboard determines its efficiency. The closer together these figures are, the less power is wasted, saving you money on your electricity bill in the long run. In the most extreme case during our testing one of the power supplies had an input/output differential of over 300W, which is highly wasteful. All the figures are outlined in our graphs, both in percentage and in actual watts.
Other additions to newer PSUs includes a 24-pin EPS style power connector, instead of the 20-in ATX power connector. This has been designed for the new Intel Pentium 4 processors, but has been a server and workstation standard for some time. Added to this is a new eight pin 12V connector, which will eventually replace the four pin 12V connector, but this is unlikely to happen for a few months yet. A six pin connector for PCI Express graphics cards should start appearing shortly as well. Some o
What? You mean you didn't know they're using the enhanced 1.1 version? It now stands for M$ HugeText Transport Protocol, and that line is mandatory here. If not, the browser thinks the server is using one of the other OSs and will crash your computer for being naughty.
Or something like that.
Carlos Martín
Well, it happened to me yesterday. I got home and my computer was off. Tried to turn in on and dead... pfff. Now there is an article in Slashdot about that, funny.
Anyhow, when I turn on the power supply, I got the blinking lights on the keyboard which tells me there is stand-by power. But I soon as I press the MOBO power button, I got about 1/3 sec power where all fans go on and then everything shuts down. No signal on monitor screen or anything. I removed all components from the power but the mobo and same... I opened the power supply but nothing was exploded or burned.
I dont have a secondary machine that I can use as a test dummy. So, is there a way to tell if the power source is toasted? I was cheking the ATX pin connectors but not sure what terminals should I jump to turn it on.
I would probably have to go to the store and get a new one to test it... bumer.
Wattage means almost nothing, the 12v rail is much more important. Looking for the magic number of at least 15amps but 18 is much better.
What I learned from my internship, which included fixing monitors: lightbulb glass is an excellent insulator for leaking capacitors.
1. Break light bulb into large concave pieces.
2. Cup piece around arcing leak of power supply.
You can get a couple more years out of a monitor if you don't mind the occasional pops and crackles.
Currently bidding on sig
I was having consistent random crashes - the computer would suddenly reboot (all the way to bios, instantly) with no warning. The only clue was it happened most often when I was doing a disk-intensive task (which meant I had several crashes while the system was writing the FAT... BAD news).
For months I troubleshot all kinds of stuff, to no avail. New mobo, new processor, rearranged hard drives, reinstalled software, new network card, you name it - one step at a time, but no effect. The crashes continued.
Finally I happened upon some similar accounts of instability and they mentioned power supplies. I thought I was okay with a 300w supply and my Athlon. Nope. As soon as I replaced it, instant stability.
Some things to note about my experiences:
I upgraded to the Antec TruePower 430. It's an extremely quiet supply, even quieter than my processor fan, with a temp-controlled variable-speed fan and a second case fan molex connector that also is temp-controlled. It rarely runs above idle, but my case is always cool. That alone was worth the upgrade price.
I was loading the supply more than I had realized: I run dual graphics cards, two hard drives, and two CD/DVD drives. The crashes were apparently caused by the hard drives - it's apparently well-known (in some circles) that the highest instantaneous current draw in a PC is when the hard drive head starts to seek (lots of current is needed to get rapid motion and get the seek times down). So anytime I was doing a disk-to-disk operation - like a backup or CD burning - I was loading the power supply dangerously close to its limit. One step over the line, and the processor would hiccup. Boom, instant bad FAT table and a week of rebuilding.
Finally, this wasn't an overnight problem. I brought it on over time by adding things to my PC incrementally... hey, let's add another drive... hey, a spare graphics card... I can keep the case - it's working fine, right?
So word to the wise: get a GOOD power supply, and get one that's rated well ABOVE your expected average load. Pay attention to those current draw numbers on the hard drives; wattage alone doesn't tell the whole story, and small spikes can kill you.
--Brandon / Split Infinity Music
To tie a cheap oem 300watt power supply to a whopper of a PC that you just blew a few thousand dollars on is the biggest mistake most people make, and overlook. Dirty unreliable power supplies that feed your PC are like heart attacks waiting to happen. If you're going to invest heavily into building a new computer, do not over look your PSU. If you do a little research (other than compare maximum power to price) regarding Max power @ watt operating temperature, you'll see that most cheap PSU's are rated say 300watts, but for a nice 30 degree Celsius operating temp. Now let's think about that. How many PC's operate that cool? Also, your better built PSU's will typically weigh a lot more, because they're simply better built. Nice and heavy means beefier power supplies, larger capacitors (to give your board that extra oomph it requires when you boot, or when you load it up), and it might even mean you have PFC included--a Power filter controller. These PSU Companies aren't always out to get the consumer by the jugular.
Tom's Hardware had a roundup of 15 power supplies in January of 2004. Tom's review included things that trusted reviews left out such as noise levels. Tom's review can be seen here
Great in principle, bad in implementation? They use cheaply soldered stuff and fail really easily -- it's happened to my friends, too. Comments?
perhaps because they autosense the voltage level so there's no annoying 115V/220V switch on the back. Newegg carries them. They topped the efficiency tests in the linked review. Way, WAY more efficient than Antec True-series, and slightly more efficient than the Antec Phantom. Definitely my favorite power supply brand.
I'm currently looking at moving to a country where the regular voltage runs in the >200V range. One thing I've wondered is if the PSU's are more or less efficient at greater voltage?
In general, the best power suppy is one that matches the equipment it powers.
Take my own rig for example: The Athlon XP CPU's current is derived from the +5V line. Together with peripherals, that makes a big requirement on this line, but +12V supply isn't too critical. If CPU draws current from +12V line, things would the other way round. My PS is only 200 Watt, powering XP1800+ system. Way too small? Nope: CPU is lower-voltage type, ~50W peak rating, only 1 HDD, 1 optical drive, 1 memory module, passively cooled videocard. PS is good quality, and matches this setup well. Result: a rock-stable system. I would only consider a more powerful supply when adding extra harddisks or optical drives.
I remember a similar review, where conclusion after measuring and testing was, that the plain WEIGHT of a power supply was a better indicator than make or price (for similar wattages, that is). This because heavier resulted from thicker wires, larger cooling blocks, larger capacitors, etc., in short: heavier quality. Doesn't say everything, but a good first indicator if you're deciding between similar-looking used power supplies. Anyway, and serious tests should include stuff like efficiency, line- and load regulation, and any serious manufacturer will provide figures on those. Also don't forget fan noise.
The problem with above is that most systems aren't constants: peripherals are added, videocards upgraded and so on. My rule is to match peak consumption of components against max. ratings of the PSU, for individual lines (+5, +3.3, +12). Then the average current draw should be safe. Too bad you don't have accurate data on some components' power draw, like motherboard or videocard.
I think your experience with switching to an Antec power supply is good reason why if you're running a machine with a faster CPU and 1 GB of RAM you want to get at least a power supply of 350 W or higher made by Enermax, Antec or PC Power and Cooling. They're not cheap, but at least you're have the assurance that your machine will last a long time thanks to the power supply offering stable power to all your computer's components.
And here is the whole thing, all one page: No ad version
No suprise that Tagan won the Editor's Choice award then.
Sounds like the sort of comparison test Microsoft would commission......
People who are using the term "dirty power" have no valid opinion on PSU's.
I'm using firefox, anyone else doing so notice the page bouncing up and down a few pixels every few seconds?
I bailed on the first page over that.
-- Note: If you don't agree with me, don't bother replying. I won't read it.
The article says "With increasing power requirements the amps on the 12V rail have constantly increased, and if this had continued unchecked a PSU failure could potentially result in a fatal accident. With the new design this risk has been greatly reduced and we should see a transition to dual or even quad 12V rails on all high-rated PC power supplies this year."
What on earth is this supposed to mean? If your power supply fails only half the contents of your computer will fry?
On a car, an insurance company would call this a "total loss" and I can't quite imagine repairing a computer half of whose components had been burned out.
"How to Do Nothing," kids activities, back in print!
First - I spent the better part of 20 years designing military and aerospace switching power supplies and systems. Admittedly these toys were commercial products, but I think I'm qualified to say the following:
:) )- the latter is seldom accurate.
a) purely resistive loads are a poor model for PC load characteristics, as are purely constant-current loads. But the CC load is a tougher test.
b) transient line and load response (or lack thereof) can preclude operation at the steady-stete levels tested.
c) I just skimmed the article as it was loading strange, but I didn't note any specific cross-regulation tests. These types of tests may yield poorer performance measurements. They almost always do.
d) Testing to see if a PS will run at full load is not the same as seeing if it will START under FL. I didn't notice these tests. Likewise Starting at low or hi input is tougher that running at same.
e) we ps designers had an expression: Power supplies are like assholes - everyone has one and everyone thinks they're an expert. The former is true (some folks have two
OK - flame away. I'm gonna go eat lunch.
Cloned foods give the statement "We had that last week!" a whole new meaning.
There are much better power supply reviews available at Silent PC Review. The SPCR guys are very silent-centric, but also test the efficiency, temperature, and stress test the power supplies as well. They have many more pictures, and even analyze the heat sink and fan configuration. These Trusted Review guys aren't even close.
Seriously, I look down the list and in there I see only two names of power supplies I recognise. Where is Antec, PC Power and Cooling, Fotron/Sparkel, or any of the other extremely common and popular powersupplies (ok, maybe PC P&C isn't popular, but they are the reference for many geeks)?
Also where are noise graphs? That's probably one of the most important features for me when buying a power supply. Wattage is easy to deal with, I just overspec, most self builders do. It's amazing at the tiny power supplies that systems we order from OEMs come with, and they operate fine, they are just running much closer to their limit than I run mine. The important question is how much noise will the PSU make. They talk a little about it, but don't actually test it.
They also failed to include a cirtical test: What happens if you drive the PSU past it's capabilities? Ok, so you should always overspec and this shouldn't be a problem, but hey, it can happen. So what does it do? Good ones will just shut themselves down. Bad ones will catch fire, which actually happened to a guy here. Along those lines, how do they deal with a fan going out? Do they refuse to power on, power on, but cut out when temperatures get too high? Just burn up? How about if there's a shorted wire inside the case (it happens)?
I'm less interested in knowing how they perform, powerwise, under load and more interested in knowing how loud they are, and how well they'll protect the system in the event of a failure. Only once I'm sure the PSU is going to deal with failures in an acceptable way and produce low enough noise to be tolerable do I want to look at how well it copes with heavy loads. I'd rather just get a bigger one and load it less if it means on the chance I DO overload it, it won't burn my computer up.
The output power rating, which is what you need for operation, is based on a combination of the outputs that can be simultaneously loaded.
The efficiency of a power supply is also dependent on the load being used. For instance, the main regulation feedback loop probably has the highest efficiency and the other outputs have secondary post-regulators that require more background power to operate.
Power supplies operate from a 120 volt or 220 volt input AC wall plug/outlet and undergo some severe transients at turn-on and turn-off. Some of the supplies have automatic voltage sensing circuits to operate from either of these inputs automatically. Nearly all power supplies operate from an internal 340 VDC. This voltage has to start from zero and return to zero when unplugged. Most present power supplies have a keep-alive circuit to allow instant on from a standby condition. (The green wire on the output side.) Don't mess with the green wire with yellow stripe that is on the input side. That one is a safety wire for the input protection.
A WORD of CAUTION: Give your power supply a chance! Design engineers cannot anticipate and design in protection for all conditions and still give you a power supply you can afford. When you turn it off, wait 10 seconds before restarting so that capacitors can discharge and voltages can settle to stable conditions. You may never be able to make a power supply fail if you don't, but you will not be happy if you do. I have designed power supplies, purchased, and tested PC and custom power supplies. I have two bad hard drives from a system I bought from DELL last year. A friend could not tell that the system turned on (too quiet) so he pushed the power on/off too rapidly and too many times. Twenty years ago,my first computer suffered a power supply failure when I turned it off and immediately changed my mind and turned it back on.
"Stress test" is the de facto term. The contemporary U.S. torture scandals make this topic quite tasteless to my senses.
I didn't really recognize the brands tested. These guys aren't in the USA, are they? Here in Western NY state allied, enermax, enlight, forton are common brands. Be nice to see some of these evaluated so I don't have to.
Power supply tests typically have major shortcomings. They test only a few power supplies, usually the ones that are most heavily advertised, and therefore are the most expensive.
The power supplies in the review are available in the UK, and are from only 12 manufacturers. Most of them are so shockingly expensive that there would never be a case in which it was sensible to buy them.
How about a 300 Watt Power supply from a recognized manufacturer for $18.00 delivered in the U.S.? Need 600 Watts? Use two.
One thing you absolutely require: Dual fans. Two fans prevent uncooled areas in the power supply. Also, if one fan slows down, the other may keep the P.S. from failing.
Looking up HIPER in the UL database, HIPER has a few products listed, but none of them are computer power supplies. So that's a brand to avoid.
Consistently, every power supply with a valid UL mark passed. And every power supply that blew up lacked a valid UL mark.
UL tests power supplies by loading them up to their rated load at their maximum rated temperature and running them for hours or days. They also test for safe behavior if short circuited, overloaded, or overvoltaged. They're not concerned with power quality, just safety. The device must not blow up or catch fire, even after a single component failure.
Report phony UL marks to UL at 1-877-UL-HELPS (854-3577). They arrange for seizure at U.S. Customs, and catch about $12 million a year of hazardous components, which are then crushed.
I personally would say that a PS should be underspec'd in it's reported wattage. That is to say if it reports it's wattage as 400 watts that should be a level it can sustain full time for it's expected life. Maybe that means the real limit is 450 watts, whatever. The maximum rating ought to be a useful maximum.
Like with good, profesisonal, poweramps, they'll give you a power rating. That's the RMS power they can output into an 8ohm load (usually, sometimes they spec other loads too) for an extended period of time. The amp is actually capable of more power than that, however if driven that hard it produces excessive distortion and can hurt the amp.
So I don't think it's necessiarly a flaw that others don't shut down at their rated load, it could just mean the rating is conservative. However you need to test them and find out what the true max is, adn if they shut down after that, or fail in more problematic ways.
Any remotely decent PSU should cope fine with being set to 110V and powered on when plugged into 240. It should simply refuse to power on - and at the *very* worst the PSU its self should fail.
... where's the power switch... <continues fumbling> *BANG*") and it's *loud*. Astonishingly, even with this abuse the only damaged components of the system were the PSU (duh!), motherboard, and video card.
What's a real killer is switching them from 110 to 240 while they're *on*. I've seen this done ("uh
Remember that most PSUs can take a 6000V spike for a very short period, and many times that for even shorter times. Most decent PSUs will just power off when the line is hit by lightning, for example (most lightning damage to PCs is via modems and sometimes ethernet).
Based on the name of the article, I thought they were hooking the power supplies up to someone's genitals.
As TR admits, these reviews were conducted at Maxpoint's facilities in Germany where they make Tagan PSUs. A Tagan PSU won the group test.
Nanopoint has been shopping round most of the UK magazines and web sites trying to get them to go to Germany for the same thing, heavily pushing Tagan's products. At least one UK magazine did a similar group test and, surprise, Tagan won that too.
Maybe Tagan just make really good products, but it doesn't come across as the most impartial group test ever written.
I have a 380W Antec trupower loaded all the way to its maximum output. This is one PSU that can take a beating.
Dual Athlon MPs
4-drive RAID on a 3ware controller
two TV cards, one sound card
Gigabit NIC
basic geforce4-mx video card
Multiple 120mm fans
It's a home media server and it's using every bit of that 380-watt capacity. It has never diplayed one bit of weirdness.
I'll definitely buy another Trupower. Historically I've used those and the Enermax PSUs. I don't have any Enermax models loaded up quite that heavily, but that modestly-sized Antec has really earned its bones.
Even if a man chops off your hand with a sword, you still have two nice, sharp bones to stick in his eyes.
The link you provided is OK. Just a few comments for those who bothered reading it:
The guy is obviously a musician, not a HiFi guy. Nothing wrong with that, although the two camps do have slightly different priorities in their respective quest for good sound. Each will tolerate some things the other won't, but good is good and bad is bad.
The Peak Power ratings he alluded to in the webpage for home audio equipment from the 70's ended (in the USA and Europe) because they were basically outlawed as being too misleading to consumers. They can still be mentioned, but RMS values must be prominent. There is such a thing as IEC peak power ratings, which at least does have a methodology to get the values. If it doesn't say it's IEC rated then it isn't, and the numbers are pure science fiction.
Without getting into too much detail, the FCC in the US ruled that "portable" audio can still use the "old lies" while non-portable audio must adhere to the RMS regulations. Although it might appear that anything that plugs into AC wall sockets is not portable, that's not true under the regulation. Basically, if it is not designed for permanent installation in a building or it it has a handle, it's portable, whether it can run on batteries or not.
Car Stereos, Blasters & Boom Boxes, and Computer Speakers are all "portable" and can use all kinds of inflated (compared to RMS) values for power output. TVs are "portable" if they have a handle on them, and most do, even if they're 150 pounds with 36" screens.
Power Ratings on loudspeakers (some posts in this subtopic mention them) are different altogether. There is no acceptable way to rate a speaker for power output in watts. Responsible manufacturers will offer a recommendation for power input. Even then, it's only a rather vague guide that depends on how they are used.
Speakers do not "put out power" in watts; they only accept power you deliver at a less than perfect efficiency, wasting the rest as heat. The "heat" is what usually blows them up and although too much excursion will cause a failure as well, it will only get that far if they are getting clean power to begin with. See JBL's PDF (3 pages) here:
http://www.jblpro.com/pub/technote/spkpwfaq.pdf/
Back on to the Parent Post:
Power supplies are expensive devices, comparatively. There are very few ways to get good, solid, output out of a power supply, and for the most part the solution is to add cubic dollars. They are simple devices, electrically, and everyone knows the "secrets". That's not to say an expensive PS is always good (they can just charge more) but it's very difficult to get good output from inexpensive devices; and I would suggest without tradeoffs (which may fit your intended use perfectly, or not at all) it's impossible.
for a second there I read that as Trump-power, and thought wow! that must be the best power supply... anywhere!
The link you provided is OK. Just a few comments for those who bothered reading it:
The guy is obviously a musician, not a HiFi guy. Nothing wrong with that, although the two camps do have slightly different priorities in their respective quest for good sound. Each will tolerate some things the other won't, but good is good and bad is bad.
Actually Rod Elliot (the guy who runs that site, The Audio Pages) can be considered a HiFi guy; he has a lot of info and schematics for audio gears of all kind (most quite good, i've built a few) - yet he keeps it all scientific and objective instead of falling for snake oil ("magic" audio cables, burn-in, bizarre gadgets, etc). In a way, it's a refreshing read if you're into HiFi. His article on PMPO ratings is dead on, IMHO.
As for speakers ratings, you're right. Basically, the max power input rated for a speaker is the one that the coil wire will take sustainedly before self destroying; the efficiency, which is measured in dB/W, can vary wildly and depends on a gazillon things. A 40W speaker might take short passages of 50-60W but will destroy itself with a 100W amplifier. It's not easy to measure the power output of a speaker, but it's a (small) fraction of the power input.
And PSUs... well, since PSUs became available for as cheap as $15 bucks, the build quality has obviously gone downhill. I use two powersupplies in my main system - the second one is an old AT 300w psu (turned on by the main one) which feeds all drives. This ended all my griefs with power.
This review sux. Where are all the popualt PSUs? Where is OCZ, Coler Master, and Thermaltake? I can continue the list of popular brand that are not listed but there is no point. My point is that the authors have chosen pretty much only the stuff that they could get their hand on and apparently did not even put enough effort in that area too. So is this a good an unbiased review. Not at all. The only thing that you might get out of it is that some manufacturers cheat too much on the specs listed and do not do proper testing of their product. Not like you couldn't figure this much out by simply thinking on the subject. After all you get what you pay for.
my Antec 350W PS died last night ... not a big fan of PSs right now
You know, I was in the industry for over 20 years. I can usually tell if someone has a musical background or a purely hifi one.
... we are talking about the same man, right?
... I have worked in the electronics, audio and of late the telecommunications industries for over 30 years, ...In case anyone was wondering, I am not an "audiophile" in the true sense of the term. I enjoy music immensely, and quality reproduction is naturally very important to me. ... or many years I had my own business, which was predominantly involved with musical instrument amps, PA systems and the like. ... I played in a few bands for a while (guitar, then bass), ... I spent quite a while mixing for live bands, and toured Australia a few times - life on the road with a rock band has to be experienced to be believed! ...
They think differently; they approach hifi differently, for example. Like I said in my parent post, that doesn't invalidate what they say. But it does give the reader a clue to their perspecitve, which is a critical aspect of evaluating any advice as it relates to your own situation.
So, after your reply, I was curious about whether I had got him wrong or not.
Google gives me Rod Elliot, Elliot Sound Products, etc
He's a musician.
From the link:
The Author: - For those brave or foolish enough to want to find out about me
Selected quotes:
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He apporoaches the subject like a sound engineer does, although he has an interest in pure reproduction at home as well, and that's exactly how he came across in your first link.
I think, considering the subject of your parent post, you chose to link to his site wisely. He'a an appropriate authority for the topic of your post.
Regards.
I've found that the most consistent and simple test regarding the quality of a given power supply is to weigh it. If it weighs more than the average power supply, it's more likely to be built with components of above-average tolerances and thus be more robust. You'll notice that all high-quality power supplies are rather hefty compared to the bargain basement ones - this isn't by accident.
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