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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 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 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.
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
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!
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!)
--ngoy
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.
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.
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.
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.