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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.
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.
Slashdotter are stupid and biased.
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
i buy them at newegg. highly recommended.
Wow, we killed tomshardware, maybe his power supply went!
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.
I'm not a prophet or a stone-age man,
I'm just a mortal with potential of a super man.
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!
"Tomorrow's forecast: a few sprinkles of genius with a chance of doom!" - Stewie Griffin
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.
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.
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.
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...
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.
Inadequate and Deceptive Product Labeling:
Comparison of 21 Power Supplies
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Full Load and Overload - Power Supply Units Pushed to the Limits
Hehe...
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...
--Won't that be grand? Computers and the programs will start thinking and the people will stop. - Dr. Walter Gibbs
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.
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?
And the men who hold high places must be the ones who start
To mold a new reality... closer to the heart
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
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.
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?
"How to Do Nothing," kids activities, back in print!
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.
From excellent karma to terible karma with a single +5 funny post...
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...
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
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.
Bruce Lane, KC7GR,
Blue Feather Technologies
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.
Ne mæg werig mod wyrde wiðstondan, ne se hreo hyge helpe gefremman.
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.
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.
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.
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.
The wheel is turning, but the hamster is dead.
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.
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.
If you wanna get rich, you know that payback is a bitch
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.