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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.
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.
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.
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.
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.
One leaves the computer plugged in for the ground. Unplugged, you won't get electrocuted, but the box won't be grounded either. You have to pick one, or find another way of grounding the box (which realy isn't that hard).
We do not recommend the models we tested from Noise Magic, PC-World and Maxtron, as none of these models offer any safety overload protection (auto cutout) and their capacitors explode with an audible "bang!" well short of their maximum rated output.
I don't know if this is the case with these power supplies or not, but some transformers are loaded to go "bang!" when they exceed tolerances so that they don't melt and fuse shut and start a fire.
Good question. My "came with the case" Antec PSU died and I replaced it with a PCP&C unit, 450W. The machine is dual P3, .5GB RAM, dual HDDs, SCSI, GForce, etc. Uses its share of power.
The most useful part of the Tom's Hardware writeup is the breakdown of estimated power consumption for a "high end" machine. Based on that, I figure the 450W part I have is just a bit over the necessary capacity. Maybe 15% or so, assuming the rating is accurate.
Anyhow, like you, I was disappointed to see Tom skip PCP&C in a rare PSU test. Sometimes I wonder a lot about Tom's. The AMD bias is obvious to me. OTOH, it's possible PCP&C wouldn't play ball and submit units for testing. Not unheard of. It's an American company, possibly with enough lawyers employed to govern a State.
Maw! Fire up the karma burner!
Not everyone is so sweet on PCP&C as you would expect. I personally just had one of theirs murder my KT7A-RAID, along with all 3 DIMMS that were installed. I'm just glad the proc, cards, and drive all lived. Along with a couple of other bad experiences, my $250 upgrade is up to about $600 now. At least I may be able to get a refund, but we'll see. I've got an RMA and I'm shipping it today.
I was wary of even using it in the first place, and there're two things I didn't like. There was no switch, and there was no vent on the bottom. I know a switch isn't technically necessary, but I really like the idea of switching off my PSU and leaving it plugged in while I tinker (grounding...). And the vent is kind of important, since the proc sits right under it...
And yes, I took all due precaution, and no, there is no obvious indicator that it is for a Dell (which are wired differently). Try a Google groups search for more experiences. No link, no time. Sorry.
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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'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.
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.
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.
"Tom's hasn't started a review unbiased in easily 2 years."
While I generally think that Tom's is biased in some respects, this example isn't the best one. (Not that I'm trying to create havoc or anything, or disagree totally with the Anonymous Coward's opinion, I'll just present my own opinion.) Realistically, most people still use a floppy drive. Although you can burn a bootable CD, CD's are still rather impractical for transferring small files to another computer. You say, why not transfer it over the network, well, if you're trying to get the newest NIC drivers to a computer that you just put the NIC into, then well you have a problem.
Next problem, the reason that 2 power connecters was suggested, was for the Radeon 9700. If you take a look at the card, you'll see that it requires an external power source, as the AGP bus isn't quite powerful enough to give it ample power. This external power connector is a Floppy Power connector. You'll probably start seeing more graphics cards like this in the coming years, unless they drastically increase the voltage supplied to the AGP slot.
If you're looking here for something insightful or thought provoking, you're probably looking in the wrong place.
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!
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Hrm.
.497 V to +5 V, 11.86 V to +12 V, -12.27 V to -12 V, and -5.04 V to -5 V.
My PSU is currently outputting 1.71 V to Core 0, 2.46 V to Core 1, 3.28 V to +3.3 V,
I can tell this all either in my BIOs or with some software I have called Motherboard Monitor or MBM for short.
Tim
Omnia vestra castrorum habetur nobis.
I used to leave the power supply plugged in to for that same reason on my ATX Abit board.
Then I dropped a screw onto the motherboard and the computer came to life! Scared the hell out of me I tell ya.
Rather than reaching for the screw and causing a short-circuit or fire destroying my brand new mb, i unplugged the machine and thanked God that my system was fine afterwards. whew...
I guess that experience is closest to working on a dead person in a morgue and have them move/come to life. hehe...
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.
I'm out of my mind right now, but feel free to leave a message.....
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.
Knowledge is power. Knowledge shared is power multiplied.
The heaviest things in a powersupply are the transformer and the massive heatsink. Of course, you will also notice a bit more heft if they don't use the cheaper thinner sheet metal for the case too.
Very simple. A larger transformer can handle more current.
A large heatsink can mean ONLY ONE THING: the powersupply needs to dissappate large amounts of power lost to inefficiency. But this can have two causes - either the PS is efficient, but truely capable of high power, or the PS is inefficient, and they're trying to palm it off to you.
Man is the animal that laughs.
And occasionally whores for Karma.
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.
That's just it, computers *ARE* getting more efficient, they are just doing a lot more. Consider how many ops/sec your current system could do, and how many your old system from 6 years ago could do.
Remember, you have the equivalent of a several Cray supercomputers circa 1972 parked on your desk. A single Cray supercomputer of that vintage drew enough current that they had to use cryogenic cooling. Not so bad in that context, huh?
You want a system that draws less power? Ditch GUI's, stick to vi and precompiled kernels, and run it on an older system.
see the fsp in the model number of the winners? fsp = fortron source power. fortron source power owns sparkle.
t =m anufactory&manufactory=1389&catalog=58&DEPA=1&sort by=14&order=1
http://www.newegg.com/app/ViewProduct.asp?submi
click 'see picture' on the 300w/$27 unit and you'll see the EXACT SAME model number as the winner.
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
There is one compelling reason to leave the power-supply plugged in when working on the system -- static.
Most folks don't use ground straps, and hence may carry a potential with respect to devices they are handling. You need not see, or feel an arc for to destroy a component!
A good supply should have a rocker switch in the back that cuts the power, but leaves earth ground intact.
This way you can power off the system (for real), and it will remain grounded. Now all you need do is keep a hand on the case at all times.
--
Matt
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.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
We have a couple of racks of process control computers - 30 or so - and I think not one of them made 2 years before the power supply fans quit. These boxes run under load 24/7. We keep a stack of supplies on the shelf and part of the PM is to see if the fans are turning. P S failures cause about as many problems as everything else put together.
Profanity - The sign of a small mind trying to express itself.
Where is Asus in brand of Elan Vital. I am using this case&power supply and said to be one of the best cases (obviously, it has no neons etc,just excellent engineering design).
Check http://www.elanvital.com.tw/
Anyone knowing it would understand why I am surprised its not on test.
This ratings-race makes it difficult to sell good quality power supplies. If they give it an honest rating, they can't compete with the $19.95 junkers that claim to have better performance. This article is a breath of fresh air, though I suspect it's not going to get the bean-counters attention, and we'll still be forced to accept power supplies from the sleaz..er, lowest bidder.
If the power supply wasn't made in the computer maker's own factory, then buyer beware! That is evidence it's cost (i.e. quality) cutting time in the accounting department.