Tom's Hardware Compares Power Supplies

Some guy wrote in to say "Tom's Hardware Guide takes a hard look at power supplies to find out if we are getting what we paid for. The results of the testing were very surprising." Very useful to anyone who has built their own machine from scratch or burned out a cheap power supply.

Comments

Power Supplies

[LordYUK]

My friend and I set fire to quite a few power supplies, mostly of the cheap variety... one was in an emachine (gah, they SUCK) after sticking a G4 ti4200 in it...

that was an accident..

the other was when he flipped the voltage on a system that wouldnt power on... that was an interesting smell, let me tell you...

Any article that has a flaming PSU is good.

[Prince_Ali]

I hope a few of those people who pay $400 for the latest and greatest video card and $15 for a power supply read this.

Fireworks

[RobPiano]

I had my computer for 3 years. Never once had a problem with it. My dad decided to install extra memory on it. It literally caught on fire.

I know you're thinking novice... But he's a software engineer, and has worked with a computer since the transitor moving days.

Lesson to be learned:
Buy cheap powersupplies, and give them to your eniemes as presents.

Rob(ert) #3

Re:Fireworks

[Anonymous Coward]

I know you're thinking novice... But he's a software engineer


You learned the wrong lesson.

Lesson to be learned:
Never, Never, Never let a software engineer touch the hardware.

Re:Fireworks

[ngoy]

Since I am from the old school of computing technology (where off is actually off, none of this soft-on/off crap) it surprised me when I was putting in some dimms into a friend's HP that the RAM slots were powered for some reason (no, it was not in sleep mode). I pushed on the dimm and suddenly saw a bright point of light and little puff of smoke. I yanked the dimm out, only to find that one of the gold traces on the dim got so hot it melted the epoxy (or whatever holds it onto the pcb) that held it on and soldered itself to the dimm slot on the pc. So I ended up using a twice as large dimm in the other slot.

Moral of the story is unplug the power cable (we all do that don't we). Nothing gets your heart going like electricity! Like the time I was putting in a gable fan in my attic and cut a live wire with my T-Cutter's. THAT was a bigger spark, and burnt a nice big hole in the cutters. At least I got to exchange them at Home Depot

ngoy
(I'm still alive! Darwin ain't got nothin' on me!)

Re:Fireworks

[Neon Spiral Injector]

Yeah, the new ATX specs have power going to the board as long as the cord is in the wall. I was from the AT crowd too, I had actually been taught that a power supply plugged into a grounded socket was a good thing to leave when working inside the computer.

Luckly my surprise with the new ATX stuff wasn't as bad, I just had a machine power up when inserting a video card. No damage done.

To keep this a bit more on topic too, most good power supplies have a hard switch (as opposed to the soft one that the ATX power button triggers) on the back that will keep all current out of the motherboard.

Re:Fireworks

[ewhac]

Lesson to be learned:
Never, Never, Never let a software engineer touch the hardware.

The software guys at NTG -- myself included -- had this habit of wandering into the hardware lab and taking up space just to kill time and/or clear their thoughts, sometimes idly frobbing tools. Drove the HW guys mad.

Actual overheard statement, delivered to wandering SW guy from head HW lab tech in police officer-voice: "DROP THE SCREWDRIVER! PUT DOWN THE SCREWDRIVER AND WALK AWAY!"

Schwab

Re:Fireworks

[dildatron]

You are correct. I like to either lick the chassis and keep my tongue touching, or keep my nipple pressed against the chassis while I am installing/removing cards.

sparkle power supplies

[mackstann]

i use sparkle power supplies. they are second only to pc power & cooling, and they dont cost an arm and a leg (pcp&c do!)

i buy them at newegg. highly recommended.

Re:sparkle power supplies

[NetFu]

I'm sorry, but I work for the number one power supply distributor in the USA (we're not a direct reseller, though) and Sparkle power supplies are the BIGGEST pieces of sh*t I've ever had the misfortune of touching. They are extremely prone to failure -- as high as 10-25% out of the 20-25 we've bought for I.T. use (I'm the Director of I.S.) and we have lots of manufacturers who replace failed Sparkle power supplies with others that we sell.

Yes, they're cheap, BUT you'd better buy two for every machine you use them in (one for backup) just to save you the trip to your local Fry's (or whatever your local computer hardware reseller is) for a replacement WHEN it fails.

And to top it all off, most Chinese power supply companies (like Sparkle) feel that 10-20% failure rates are ACCEPTABLE! This is in an industry where a 1% failure rate usually sends the engineers back to the drawing boards. Sparkle Power is a huge joke in our industry...

Re:sparkle power supplies

[Stephen Maturin]

Whatever you say, fishbulb....

Re:sparkle power supplies

[Verteiron]

I've had excellent luck with Antec PSUs. I've got the 420W one in my system with 5 IDE HDDs, 2 cd-roms and a zip drive. One of the things I really like about it is that it comes with two special extra connectors for fans. Any fan hooked up to them will be speed-regulated like the units internal exhaust fans. This can really make your whole system a lot quieter. Antec costs a little more than average, but they are constructed well and come with excellent documentation.

Re:sparkle power supplies

[Anonymous Coward]

I've been running a small computer store for almost three years, and we started out using nothing but Sparkle power supplies, and out of the several hundred systems we built with them, only one died - when a storm knocked over a tree, which fell into a power line, which, well I'm not sure of all the details, but end result was that anything plugged in to an outlet in half of the customer's house was completely fried. Satellite receiver, stereo, TV's, etc, and computer; most of this stuff was plugged into cheap "surge-protectors" too. In any case, none of the components in the computer were damaged - swapped PSU's and it was up and running.

We briefly switched to Deer, mostly because we got a really good deal on some cheap generic cases that came with the Deer supplies. No kidding the failure rate was over ten percent, but we only sold about 120 of these, so it's maybe not a great sample. But friends at another, larger store across town said that at least half of the supplies in the first batch of cases they ordered died within four months. Needless to say that was also the last batch of those cases.

Another thing - one customer who lived in an upstairs apartment in an older house had problems from day one - crashes, freezes, you name it. Every time he brought it in for service, though, it worked great. Right away we suspected PSU, and so we swapped in a Sparkle on his second visit - I talked to him a couple of months later and he hadn't had a single problem since. Similar things happened to a lot of rural users as well.

Why trust Sparkle? If I remember correctly, they make power supplies that are used in hospital equipment such as Dialysis machines and "Iron Lungs." These, obviously, have to be reliable, so the company definitely has the know-how, even though the PC PSU's are undoubtedly held to lower standards. They aren't cheap, but they aren't the most expensive on the market, either.

In the end, we settled on Antec equipment, not for any problems with Sparkle, but because it was difficult to get a decent case sans-PSU to put the Sparkle's into. We've yet to see one of these come back dead, either - since we started using them, we've sold over three hundred. That's a pretty good record for both companies, if you ask me.

Re:sparkle power supplies

[XorNand]

I second the recommendation for PC Power and Cooling. I got tired of going through a PS every 6 months, having themburn-up or worse; the bushings would start to fail and it would sound like a turbine engine until it warmed up. As far a price goes; it's a matter of perspective. I think I paid around $200 for my high-perf 350W supply about 5 years ago. To date, it's the only piece that I haven't upgraded or replaced in my system (including the case). Spend twice that amount for the latest bleeding-edge graphics card and see if you still have it half for half as long.

Re: Sparkle Power Supplies

[person-0.9a]

Kind of a bummer name they picked. The top three things things I do not want my Power Supply to do:

- Flame
- Smoke
- Sparkle

dead toms.

[lamp77]

Wow, we killed tomshardware, maybe his power supply went!

Good and QUIET!

[xanadu-xtroot.com]

I bought this power supply about a year ago. Not only is it as quiet as they tout, it's been a real work horse for me. I have a Lian-Li case, all drive bays filled (from time to time, not constanly ALL hooked up, but...), this thing keeps on running.

I highly recomend checking these folks out.

Marketing lessons from audio amps?

[Rob Parkhill]

It sounds as if power supply makers are taking a marketing lesson from audio amplifier companies... bigger is better, and no-one ever actually verifies those numbers.

My favorite was a $25 amp car audio amp I bought about 10 years ago. I kid you not, this thing is about 2x the size of a deck of cards, and is rated at 500W per channel. Ha ha ha ha! No, I didn't buy it for it's amazing power, I bought it because it was $25 and I needed a cheap amp for some tinkering!

Re:Marketing lessons from audio amps?

[afidel]

They might not be lying, peak to peak for one cycle it might be able to output 500W (just before it explodes). Of course most respectable amp manufacturers will list the RMS watage number tested by an independant lab. I think it was funny one time when a friend was laughed at by some rice boys because he had a 100W amp, what those kids didn't realize was that this was a competition quality amp and that 100W was a true 100W RMS with a peak to peak measurement of well over 1000W!

Re:Marketing lessons from audio amps?

[Lumpy]

and it's ratings were accurate.

It was more than likely rated at 500watts Peak and did not mention a THD rating at that wattage.

Car audio is usually marketed at truthful levels. Pyramid (I think that's how they spelled it) amps were usually rated at thousands of watts. but if you look it is rated as peak not RMS and it's THD was at 5%.

now an amp that sounds great is rated at 0.05%THD at RMS watts. a 100watt RMS at 0.05%THD will knock your socks off with a pair of 15" woofers in an isobarik enclosure.

the moral? read and UNDERSTAND the specs... car audio makers bank on the fact that the large number of cunsumers are too dim to understand the markings on the box.

Non-custom built power supplies poor?

[ohboy-sleep]

Users who stand to fare the worst are those who have purchased their computer from a computer super store and/or discount retailer. These systems are generally fitted with cheaply made, low-cost power supplies, which often can sustain damage even under minimal loads.

I realize that me and the half of my friends and family that are not hardware-savvy only make up a small sampling. But none of the people that I know that have bought pre-built machines have had a problem with power supplies. Whereas at work, where my office is filled with machines constructed from the parts of other machines, we've had two instances of power supply failure.

Of course the machines at the office are older and are used more often than the home-based ones, but I figured I'd put in my 2 cents.

Re:Non-custom built power supplies poor?

[Kevin Stevens]

Well I think this comes back to the fact that most people only use their machine to surf the web and read email. I think it is a fair guess that most of these people have onboard video or an otherwise anemic card, along with a 5400rpm HD, etc. Also, unlike business machines which are usually on 24 hours a day for their entire lifespans, I would say most home computers are not on as much and maybe more importantly- recieve less use as they get older and get relegated as a secondary machine in a house. I would say very few home machines get used for much more than word, websurfing and file sharing nowadays, which is a breeze for todays, yesterday's and even two years ago processors. This is a bit of a stretch, but I worked for a company that regularly made use of upgrades to extend the life of a machine... adding second disk drives, upgrading the processor, ram, etc... but of course never even thinking about upgrading the PS. I can not say how prevalent this is in other companies, but if it is, that could be another reason the PS's are overloaded and thus fail.

Re:Non-custom built power supplies poor?

[Tailhook]

It's a question of usage patterns and necessary capacity. The common Best Buy PC used in a typical manner does not tax a garden variety Chinese PSU enough to ruin it.

A SMP box with a Gig or more of RAM, used to compile kernels, run FPSs at high resolution, host a couple extra drives of various sorts, get frequently booted between multiple OSes (startup loads are extraordinary,) run benchmarks, and basically do a bunch of other crap, will need a LOT more power. I fried an Antec 300W PSU in 3 months like this. Give yourself a fright and watch the case temperature during a FreeBSD "makeworld" sometime.

Tom's caters to people that push high end hardware to it's limit. You're basically reading hotrod magazine and wondering what's wrong with your Accord.

Missing Test Equipment

[CMiYC]

I don't think these were fair tests. I would have liked to seen some oscilloscope measurements of what the voltages/waveforms looked like under full load. Being that we expect our DC power supply to delivery a DC voltage, even a novice can tell a "bad" output from a "good" output. Take two power supplies for example. A 300W and a 500W supply. (For numbers sake, let's say they only deliver 5V to the load. No +12v, -12v, etc). If I max load the 300W supply and it is delivering a clean 5volts, that's a great supply. But if the 500W supply is spiking or has considerable noise with a 300W load, who cares if it runs up to 500W?

To me that's almost more important than if the supply shuts itself down or not. Which, by the way, is still a nice FEATURE.

Re:Missing Test Equipment

[mark_anderson]

CMiYC has an important point. There's a lot more to a power supply than simply providing lots of DC current. Tom's Hardware used a constant load. Computers, especially CPUs do not form a constant load. A cpu may increase its consumption by a factor of 10 almost instantaneously. This can happen everytime the scheduler goes from the idle loop to running a cpu intensive task. The motherboard regulation will absorb some of this, but not all. The PSU must be able to respond to these surges without significant ripple or spikes. This requires good capacitors, and may require tuning the switcher frequency to improve the response.

You get what you pay for

[Pedrito]

This applies particularly to power supplies. Sure, CPUs and memory, but the prices aren't nearly as fixed as they are for power supplies. Really, with power supplies, the price range doesn't vary much and the good ones tend to cost (though there are some decent ones for decent prices).

Before I came to my company, they bought a bunch of no-name PCs. There must have been a motherboard flaw that caused them to burn out power supplies and they kept replacing them with cheap supplies which couldn't handle whatever the motherboard was doing, and they would burn out too. Out of about 8 machines, I think we went through 14 power supplies in two years.

You'd always hear, "What's that burning smell?" "Did you check the back of your machine? I think that's smoke from your power supply."

I ALWAYS get a decent supply and have NEVER had problems, even when I lived in Mexico and had pretty questionable electricity.

Re:You get what you pay for

[Tackhead]

> This applies particularly to power supplies. Sure, CPUs and memory, but the prices aren't nearly as fixed as they are for power supplies. Really, with power supplies, the price range doesn't vary much and the good ones tend to cost (though there are some decent ones for decent prices).

Very true. The problem's one of brand differentiation.

At the low end (vast majority), there's Joe Sixpack, who doesn't know anything about what's inside his box, and who doesn't even think there are modular components in it. "Dude! I got a Dell!"

At the midrange (20%), there's most of us. "It's an ASUS or ABit mobo, an AMD/Intel CPU, and an nVIDIA or ATI card. Umm, and a power supply that came with the box."

At the high end (5%), there's folks who know that no-name power supplies suck (IMHO) and Enermax rox (IMHO). But only because we've read from...

...the really high end (1%), which are the folks who know why one brand/design beats another - say, under-rated capacitors, or a design flaw that results in the switchmode transistor getting shorted in the event of a failure of the +12V or the +5V standby line, and is typically present on the $15 fly-by-night power supplies but not on most of the $50+ brand names.

Unlike ATI-vs-nVIDIA, where the midrange and high-end folks can plunk in an "upgraded" video card and immediately see the difference between "good" brands and "shitty" card manufacturers, brand names in power supplies have trouble gaining traction, because while they're working, they're indistinguishable from each other.

And of course, when they stop working, it's too late. For that reason, always keep a spare supply handy. Even a "free" no-name supply ($5 bucks from a surplus store) will last you a week until your "real" power supply arrives from the web merchant.

Rule of thumb: Put your hand over the PS's exhaust fan. If the air's significantly warmer than the air in the PC's case, get a bigger power supply.

(I learned it the easy way - a d00d at work got a dual Athlon mobo and just tossed it into his old case, and wondered why it was so warm under his desk while his CPU temperatures were normal. Answer: 2-year old 300W supply + dual athlon + two 7200 RPM disks = one massively overloaded P/S. We threw in a 365W "spare" for the weekend and ordered a 450W that got there by Monday. Air flow out the back was much cooler. Frankly, I'm amazed the 300W supply was even able to boot before blowing itself to hell.)

Useful Related Link...

[TheGreenGoogler]

Over at "The PC Guide," there is a comprehensive look at issues related to the output power capacity and ratings of power supplies. I found it to be very informative... The link can be found here...

Antec Power Supply

[delta407]

I recently bought a 430-watt Antec power supply, and it is a beast. It has two temperature-sensitive fans, gold plated connectors, and weighs about four or five times more than the one it was replacing. It was well worth the money, especially given the system it powers -- two CPUs, a GeForce 4 Ti, two optical drives, and a handful of modern hard disks.

On the plus side, my system is more stable, runs cooler, and is quieter than it was before. I greatly favor my premium power supply over the one that came with my case, and I strongly recommend anyone with a downed PSU to pay the extra dollar.

Re:Antec Power Supply

[Neon Spiral Injector]

I was wondering why Tom didn't review any Antec PSes. That is all I use these days, and have been very happy with them.

Not only do they have varible speed fans in them, but they have a 2 wire lead to run 3 case fans (I only have 2) at varible speed.

With the front fans of the Lian-Li case that blow over the hard drives that are variable on their own, my machine is pretty quiet when doing nothing, but comes up to a nice wurr when compiling the newest glibc with "make -j2" (yes, I know it isn't parallel safe, but you only have to do it twice to catch the one file that hangs things up).

Re:Antec Power Supply

[Dr. Manhattan]

Just a couple weeks ago I finally got the money together and stuck an Antec 300W power supply in my machine (ASUS P5A, K6-II/500, Geforce 2 MX400, etc., etc.). It had been unstable ever since I put in the Geforce, in both Linux and Windows. Unplugging a couple of peripherals (a CD-RW and a floppy drive) seemed to help.

Since the 300W one went in (replacing an old 235W) it's been rock solid, even with the CDRW and floppy reattached. Now if I only had time to play games...

Re:Antec Power Supply

[jpaz]

I've been a big fan of Antec. Never had one of their power supplies go bad. Very reliable.

Side note: I'm also a big fan of Antec's computer cases. High quality, sturdy, well designed. Antec's cases also have Antec's power supplies. You can't go wrong with Antec.

I'm not employed by Antec, but simply a satisfied customer.

Re:Antec Power Supply

[wilburdg]

I also recently purchased an antec power supply.

I purchased the SL350 power supply, from their solution series.

For a little less money than the True series, it has dual temperature sensitive fans, with plenty of power for a fully loaded system, yet runs quietly.

I payed about $50 for it from googlegear, and I have been very impressed with the noise/heat/performance.

Re:Antec Power Supply

[skeedlelee]

Actually they did review one Antec powersupply (the True380 I think). It came in just behind the leaders, though not for any reason I could tell from their spec's. Seems to have performed at manufavctures specification and was reasonably quite. Maybe they didn't think it was quite as good a deal. It was nice to see one of the readily availible brands come in near the top though.

Actually, I was curious, if you're using a lot of Antec supplies could you tell me what the practical difference, if any, is between Antec's True power supply line and their Sl line? Is it just that the tolerances on the voltages are a little tighter?

Re:Antec Power Supply

[Neon Spiral Injector]

I believe that the SLs don't have ATX12V and the Trues do. Since I deal mostly with dual CPU motherboards the ATX12V is what I need.

The TruePower series also have "bling-bling gold grills" as my co-worker put it.

Power error?

[mikers]

Inadequate and Deceptive Product Labeling:
Comparison of 21 Power Supplies

[an error occurred while processing this directive]

Full Load and Overload - Power Supply Units Pushed to the Limits

Hehe...

Good article, wish I could have written it!

[Arcturax]

I bet it was so much fun, they do reviews like this a lot more often. I know I would if I got paid to try to blow something up.

I remember blowing a power supply on an Apple IIe once as I turned it on. Scared the shit out of me too! Since then I've never had any more trouble with the supplies in Apple's Macintosh computers (which weren't reviewed here, but seem fairly solid nonetheless). I did once get a nice big fucking jolt off of one of their monitors though, numbed my right arm to the elbow and left my right side sore for a couple days from the violent muscle spasm it caused. Had it been my left arm, I probably wouldn't be typing this right now...

Tomshardware

[Anonymous Coward]

A single floppy connector, as supplied by Engelking and Coba, is not enough. You will need at least two of these.

Haven't given them a thought in over a year. All their "reviews" tend to shine highly on the products that fit "their" personal views. I mean jesus, any place that thinks you should have 2 (two) floppy drive power connectors is a little behind the times. Most people don't even use 1 floppy, let alone 2. And for all you people who weren't aware, a reviewer is supposed to enter a situation unbiased. Tom's hasn't started a review unbiased in easily 2 years.

Re:Tomshardware

[Dynedain]

Other devices do use floppy power connectors.

For instance, the head unit for my Creative SBLive 5.1 Platinum and various casemod toys like temperature monitors, fan speed indicators, etc.

No PC Power and Cooling?

[LordNimon]

The only decent third-party manufacturer of power supplies that I (and I presume most people) have every heard of is PC Power and Cooling. It doesn't appear that this article covers any of their products. Am I missing something?

Re:No PC Power and Cooling?

[mackstann]

you are not missing anything, unfortunately.

this review is pretty lame IMO, they failed to review: both sparkle and pc power & cooling, probably two of the highest regarded names in power supplies, while at the same time they reviewed such no-name junk as "engelking", "coba", "channel well", "scs", "task", and "levicom".

and the summary is also quite worthless. basically they recommend 3 no-name brands as the "winners", no one is going to buy these due to availability and/or fear of no-name brands, while THG also recommends antec psu's to those who cannot find the others, which is also stupid because people already buy antecs in droves.

also we have the issue of rebranding. many power supplies on the market are simply rebranded no-name power supplies, how do we know that just because one "herolchi" power supply tested well, all others will also be top quality? the different herolchi models could be from completely different manufacturers!

Only one of each tested

[f97tosc]

That is not a very large sample. I wonder how much specs vary between individual units of the same make and model.

In particular, it would not surprise me if there are unit-to-unit variations in noise and the power at which they give up.

Tor

often overlooked...

[jaredcoleman]

The #1 reason that I have seen for hardware failure was that the PS fan had stopped working and no one noticed. Most PC's (bought or built) are designed to pull air in the front of the machine because of the vaccuum created by the PS exhaust fan. No air flow = stagnant hot air = hot heatsinks = hot chips = CRASH. This is a very important component that is often overlooked.

PSU Fans versus CPU Fans

[Hayzeus]

On a slightly unrelated note, I've noticed that I've continually had problems with CPU fans (usually of the cheaper variety) dying a fairly early death. However, even on the cheapest of PSUs this has never been an issue for me. Does this jibe with anyone else's experience? If so, why might this be the case? Does the smaller CPU fan size somehow increase the expense of providing decent bearings?

NO SPECS for boards, no overload indicators...

[dpbsmith]

Something I've been ranting about for years: It's not just that power supplies are rated in "music watts." It's also that basic engineering apparently went out the window when micros came in--and has never come back.

Why isn't every board and component clearly marked with its power consumption?

Why isn't every system clearly marked with the amount of power available to devices on the bus (power supply minus consumption of preinstalled components?)

Why isn't there some kind of built-in INDICATOR that WARNS you when the drain is approaching the power supply capability?

None of this is rocket science. It requires fourth grade arithmetic, a multimeter, and a little honesty.

On minicomputers, the power supply was sized for the worst-case set of boards that could be installed in it. That's probably too much to expect from PC vendors, but at the very least there should be an easy way to TELL.

"This is a real good power supply and it should be OK unless you put in an awful lot of boards that take a lot of power" just isn't the way to do things.

We expect this stuff to be clearly marked on our light bulbs, our vacuum cleaners, and our fuse boxes. Why shouldn't we expect it in our computers?

Dual PSU's

[twoslice]

Actually, I wish more case designs supported dual PSU's as the power supplies these days are relatively cheap and I could use the redundancy and extra oumph.

PS Diagonistics?

[Masem]

I'm surprised that in this day and age, where your power supply is becoming one of the more critical components to keep track of (along with the CPU and GPU temperatures), that there's yet to be a way to monitor the performance of the PS with hardware/software monitors, short of wiring your own. That is, just like you can monitor temperatures and fan speeds with most modern mobos, the power supply is completely independant of this. Yes, it would require some standardization of how that info is sent and a plug on the mobo (most likely situated near where most USB/KB/M cutouts are as to avoid a 20ft wire to get it to the northbridge site), but it would seem to me to be really useful information to determine the PS health beyond the current hope-n-pray methods...

Re:PS Diagonistics?

[TheOnlyCoolTim]

Hrm.

My PSU is currently outputting 1.71 V to Core 0, 2.46 V to Core 1, 3.28 V to +3.3 V, .497 V to +5 V, 11.86 V to +12 V, -12.27 V to -12 V, and -5.04 V to -5 V.

I can tell this all either in my BIOs or with some software I have called Motherboard Monitor or MBM for short.

Tim

Could have done better...

[KC7GR]

For my part, I would have liked to have seen THG use a true electronic load for their testing. Something from Transistor Devices 'Dynaload' line would, I think, have been a much more accurate (if more expensive) choice than a box full of power resistors.

They should also have used a good O-scope to take a look at the power output waveforms while under load. I've seen a number of cases where a switching supply will look perfectly clean under low-to-medium loads, and then start to spike and freak out under higher loads. 'Tis a nasty thing to behold, and it can cause problems that can drive techs who don't know what to look for absolutely batty.

Also, others have mentioned that PC Power and Cooling was left out of the review for reasons unknown. I would guess that it was price. If so, all I can say is "How highly do you value your hardware?"

Clean and adequate power is the ONE factor that can cause more woes than any other. You can have the slickest quad-processor-super-Linux-cluster-RAID-whatever on the planet, and it won't do you one whit of good if you've got dirty power feeding it.

+5, Informative?!?! (Mod the parent DOWN!)

[csnydermvpsoft]

I've been looking for a solid Power Supply review for a few days now. Thanks Tom.

That's very informative information. I always wanted to know that you were looking for a solid Power Supply review.

Geez, that's incredibly dishonest and disrespectful thing to do. Sure, you made sure that we knew it was from the article, but did you ever notice the copyright disclaimer at the bottom of their pages? They aren't making money if we read the article from another source.

I can almost understand this when a site is slashdotted, but that rarely happens to THG.

Any person that read the parent post and decided not to go to Tom's Hardware web site as a result, please do so anyways. They're surviving on advertising revenue.

More information from all manufacturers

[Raedwald]

I'm currently planning my second own-built PC, and I must echo the article's request for more (precise) electrical information from manufacturers. It is outrageous that the peak current at 12V drawn by a HDD, or the maximum current at 12V provided by a PSU, is missing from documents that call themselves 'technical specifications'.

This information is vital: it only takes a high-end PC with 3 modern HDDs (what you might use for RAID or for other multi-disk performance tricks to overload a 400W PSU. Not because it draws 400W during normal operation, but because on startup the disks draw too much current at 12V.

Re:Tom's Recommended/NOT-Recommended Power Supplie

[Tackhead]

> Since they're already quite sufficiently Slashdotted, I'd say we've given them more than enough page views.

And besides,

maybe if

Tom put more than

two or three lines

of text

on each page

and 25K of

banner ad HTML

his server

wouldn't get

slashdotted

so easily.

EMI is a problem too

[John Jorsett]

I bought a case with a built-in 400-watt power supply that swamped a nearby AM radio with a buzzsaw noise. Replacing it got rid of the problem. Power supplies aren't that expensive, so save yourself some headaches and buy a good one.

Failures should be reported to UL and CPSC

[Animats]

Power supplies that blow up or catch fire should be reported to Underwriters's Laboratories and the Consumer Product Safety Commission. These are online forms, but I'd suggest certified mail as well, with pictures. This is inexcusable.

The relevant safety standard is UL 60950 (or the identical EU 60590 in Europe), "Safety of Information Technology Equipment". One of the required tests is a full-load worst-case temperature test. No way should those units have received UL or CSA certification.

UL's certification search engine is broken today, so I can't check the power supplies listed to see if they really passed. But those certifications are public information; you can check.

Current CPSC product recalls in the computer area include PowDec power supplies for NextLevel DSL modems and several batteries for laptops. Sounds like that list needs some additions.

Spec Fudging: A Long and Sordid History

[ewhac]

If anyone from Tom's is looking in, perhaps they may want to try out this test rig we developed for testing power supplies.

Back when I was working for NTG (later acquired by 3DO), our chief hardware designer, Dave Needle, assigned one of the engineers to test power supplies. It had to supply 5V at some large number of Amps, absolutely flat, and do it on continuous duty. Dave informed me -- to my utter, youthfully naive astonishment -- that the specs on power supplies couldn't be trusted.

The test rig the engineer came up with was several low-Ohm high-wattage resistors wired in parallel, submerged in a pan of distilled water. He then turned on the juice and watched the output on a 'scope. The room where these tests were carried out came to be known as The Steam Room.

I think he went through about a dozen prospective supplies before he found one that was acceptable.

Schwab

Where do you buy these?

[alue]

Just where can you buy one of these? Who has ever heard of Verax or Herolchi, anyway? I searched on google, pricewatch, and newegg; and I couldn't find anything but a single Fortron offering.

I've always had a really hard time finding these "secret" premium low-noise components. I would love to make my desktop quieter, and I would love to believe that these products will do the job. But if they're so awesome, why doesn't anybody sell them?

eMachines Power Supplies...

[MsGeek]

These are NOTORIOUS for their tendency to burn out at the drop of a hat. However, both Sparkle and PC Power And Cooling make 145W and 180W (the latter is AMD certified) power supplies that are direct replacements for the SFX-L power supply included in the system.

EMachines are not necessarily bad machines. They just have cheap-ass power supplies and also cheap-ass hard drives. Replacing both when the machine is brand-new is a must if you want one to last for more than a few months.

How About Using LESS POWER?

[ink]

Am I the only person who is sick of computers requiring such obscene amounts of power? Newer machines have fscking radiators on them for $DIETY's sake; what's next? A heat-pump that sits outside my house to keep the environment nice and warm? In 1995, 250W was a nice, big power supply. Then, 300W, and now 500W comes along -- other consumer electronics are becomming more efficient (monitors, televisions, refridgerators, air conditioners, etc.), but computers just keep wasting more and more power.

Re:How About Using LESS POWER?

[_|()|\|]

Am I the only person who is sick of computers requiring such obscene amounts of power?

You have a choice in the matter. If you want top of the line performance, get an Athlon or a Pentium 4 (50 - 70 W) with power-hungry components. Otherwise, you can get a Celeron (25 W), a K6-III+ (20 W), or a C3 (10 W) with one hard drive and a video card that doesn't require active cooling.

I bought a little FlexATX bare-bones system that's a little smaller than a bread box. I put in a 5,400 RPM drive and a Celeron 850. The only fan is in the 100 W power supply.

Radeon 9700

[nuxx]

You know the nice brand new ATI Radeon 9700 that most people here lust over? I put one in a friend's machine recently... I was really glad for the second floppy power connector becuase then I didn't have to use the included Y cable and add more bulk inside the case. There's lots more devices that want a power connection like this, too. CF Readers, audio break out boxes, VU meters, LCD displays, etc. More connectors is generally a good thing, not a bad thing. You don't always have to use them, and cable ties are cheap.

THE WINNER ACTUALLY IS A SPARKLE POWER SUPPLY

[honold]

see the fsp in the model number of the winners? fsp = fortron source power. fortron source power owns sparkle.

http://www.newegg.com/app/ViewProduct.asp?submit =m anufactory&manufactory=1389&catalog=58&DEPA=1&sort by=14&order=1

click 'see picture' on the 300w/$27 unit and you'll see the EXACT SAME model number as the winner.

Re:don't you think?

[blincoln]

if you like pseudotechnical hogwash, incestuous relationships between advertisers and content providers, and meaningless benchmark data.

While I wouldn't flame them quite so hard, I have to agree with the spirit. THG lost all of my respect with their handling of that "hot contraband" P4 article. If I can't trust a website to tell me when they're Photoshopping their BIOS screens and shots of CPUs, how can I believe their benchmarks are genuine, or their reviews unbiased?

Dont forget to buy a quality UPS

[bogie]

Seriously, besides saving your data you need a good UPS with AVR to feed your Power supply.

If you have power that sags or has other problems, even a high quality power supply is not going to save you.

I still can't believe there was ever a time when I didn't use a UPS at home. You really will add time to the life of your computer with a good UPS. Your PC will still become outdated, but at least it will be less likely to fail.

Re:don't you think?

[blincoln]

Well, unfortunately I can't find the original thread on arstechnica (their archive search is broken). However, here's basically what happened:

Back in September, THG posted this article with the title "Hot Contraband: P4 With 3.6 GHz" and the description "For this exclusive report, THG tested CPUs of the future, bringing you benchmarks for P4s in the 3.6 GHz, 3.33 GHz and 3.06 GHz variations."

In my mind, at least, this text implies that they managed to snag some unreleased P4 chips from Intel by one way or another and benchmarked them.

However, people on several websites noticed that the shots of the BIOS screen and the photo of the chip in question looked suspicious. They were actually from much slower chips, but with the numbers arranged so that they appeared to be from 3GHz+ CPUs. The shot of the CPU on the first page, for example, that has "PC3.3G0K" in the serial number was analyzed to show that the 3s were identical, and therefore at least one of them was copied over the original number in Photoshop.

Also, suspiciously, there was no testing of the hyperthreading that will be present in released P4s that are that fast.

Eventually, THG posted an acknowledgment of the issue, but it seems kind of hollow. For one thing, the shots they show of their super-unlocked P4 are not the same chip as on the first page. For another, they admit they're using current P4 technology. So basically what the article is about is not "Here is what the 3.6GHz P4s will be like," but "Here is what *today's* P4s are like if they are overclocked to 3.6GHz." None of the benchmarks apply to the real world unless you are going to use a liquid nitrogen (or however they managed such high clockspeeds) cooling system on a current P4 instead of waiting for the real 3.6GHz models with hyperthreading.

They *could* have been honest about it and called the article "THG overclocks a P4 to 3.6GHz!" like they've done in the past, but apparently that wasn't sensationalistic enough for them. If that weren't bad enough, they waited until a ton of people called them on their deception to admit what they'd done.

Ironically, this happened only a few weeks after Tom himself wrote an editorial about some unethical former writers for his site.

Mutton dressed up as Lamb... as per usual...

[Shanep]

There is no mention in this article of ripple performance for these PSU's under their rated loads.

Ripple is the amount of AC left in the DC output of a DC power supply. Real engineers and technicians measure this and take it into consideration to assure the reliable and healthy operation of the equipment being powered. There is no point in having a PSU that can deliver the required amount of power if it is also delivering the parts in the computer noisy power that may lead to instabilities.

The PSU's that actually were able to deliver more than their rated power, may have in fact been designed so that they actually deliver low ripple power at their rated levels. With power beyond that starting to show what the designers would deem, unsatisfactory ripple levels (Ripple becomes more apparent with higher loads).

A quiet (electrical) supply is a good thing for computers of any size and seeing an article at Tom's omit this amongst pages and pages of a "test" comparison does not surprise me.

Blah blah blah. People who know better, don't read Tom's, they "do it" themselves, properly. But the chance to test 21 different PSU's is something few geeks can do, so Tom ought to get things done correctly if he is to pass his site off as a valuable technical hardware resource.

But what I think is the real killer, is that Tom tests the noise levels of these PSU's, but not the electrical noise, the audible! Which kinda shows in a glaring manner the level of technical prowess his site staff and readership posses. Hell, they had multimeters, how hard was it to at least set them to AC and read the amplitude of the ripple!

"Test results in detail" my arse.

I'm not being picky BTW, ripple testing is a must do in PSU design and testing for most applications of a DC supply. Proper "test results in detail" would have included oscilloscope printouts of the ripple, IMHO.

Phony/UL-uncertified power supplies

[Animats]

Let's go to the UL certification database (which, unfortunately, only seems to work for MS Internet Explorer), and check out the power supplies tested by Tom's Hardware.

• Engelking -- no find
• PC World -- no find
• Verax -- no find
• Noise Magic -- no find
• Chieftek -- no find
• Zalman ZM3003-APF -- Passed UL and CSA certification testing, certificates QQGQ2.E198072 (US), QQGQ8.E198072 (Canada).
• CP4 -- no find
• Antec True-380 -- Passed UL and CSA certification testing, certificates QQGQ2.E176105 (US), QQGQ8.E176105 (Canada).
• Conrad -- no power supplies found
• Levicom -- no find
• Herolchi -- no find
• TSP -- no power supplies found
• Maxtron -- no find
• Enermax EG365AX-VE -- Found Enermax EG365PX-VE(+) in database, certified for US and Canada. US certificate QQGQ2.E134014.
• SCS -- no find
• Coba -- no find
• Seaconic -- no find
• Task -- various companies use that name, no power supplies found.
• Channel Well CWT-300ATX -- Passed UL and CSA certification testing, certificates QQGQ2.E161451 (US), QQGQ8.E161451 (Canada)
• Topower TOP-320 P4 -- found Topower TOP-320y, passed UL and CSA certification testing, certificates QQGQ2.E130843 (US), QQGQ8.E130843 (Canada).
• Leadman LP-6100E - found Leadman LP-6100A through LP-6100D, but not LP-6100E. US certificate QQGQ2.E107407 for earlier models.

UL's testing agrees with Tom's Hardware. All devices that really passed UL certification were found OK by Tom's Hardware. No UL-certified device blew up, caught fire, burned out, or failed to perform at rated load. All the units that failed lacked valid UL certification. The Leadman LP-6100 E did fail under full load at Tom's Hardware, but it shut itself down properly without damage. UL hasn't rated it, although they've rated previous Leadman models.

The Tom's Hardware article shows the data plate from the Chieftek power supply, which bears a UL marking. It's not in the database. It looks like many of those power supplies have fake UL certification, and for good reason - they don't meet specs or they're outright hazardous.

So if it's not in the UL database, don't buy it. There are plenty of good power supplies that have real UL certification. Corporate shops probably should check for those phony brands and take appropriate action. And tell UL; they will take action for phony markings.