# Power Supply: ATX vs. ATX12V



## Peter_Used2know (Feb 12, 2015)

Shopping for a new power supply on newegg and their "power search" gives a choice beween "ATX" and "ATX12V". My computer is a standard HP desktop, so I'm certain the power supply is "ATX", but what does the "ATX12V" mean? There are about 4 times as many ATX12V as ATX, so I don't want to exclude, them, but I don't want to end-up getting a power supply I can't use either.


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## greenbrucelee (Apr 24, 2007)

there really isn't any difference apart from rails etc which is of no concern really. its just a new name for it really read this ATX12V vs. ATX Power Supplies - Desktop Computers

and yes your system takes ATX power supplies i.e it takes atx, atx12v and the new atx 1.3


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## Peter_Used2know (Feb 12, 2015)

Okay thanks, that's what I thought. After I posted I realized I could look it up also and there's a bit more to it than that. It had to do with the 20 or 24 pin power connector, I think but in practical terms I'm buying a good-quality but low-end PSU and so I click both categories, which is all I needed to know.

Buying this one, and hoping for but not counting on the $20.00 rebate.

CORSAIR CX series CX500 500W ATX12V v2.3 80 PLUS BRONZE Certified Active PFC Power Supply - Newegg.com


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## greenbrucelee (Apr 24, 2007)

corsair are ok but not greatm they used to be until they started using a low quality manufacturer to make them to save money.

Seasonic, xfx amd antec hcg are the best


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## Bill_Bright (Dec 17, 2004)

Most power supply brands offer several "lines" or "series" or "classes" of PSUs, from entry-level budget, to mid-class, up to top-tier quality supplies. 

Corsair, like Antec and others, used to offer nothing but top-tier PSUs but they have expanded to offer supplies across the board. So do your homework first and consider "investing" in a 80 PLUS Gold certified. Gold certified cost more up front than Bronze (or basic 80 PLUS) but, they offer better regulation and lower ripple when stressed, and lower efficiency ratings (lower is better) which, over the life of the PSU, can result ultimately in lower energy costs.


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## Peter_Used2know (Feb 12, 2015)

Bill_Bright said:


> Most power supply brands offer several "lines" or "series" or "classes" of PSUs, from entry-level budget, to mid-class, up to top-tier quality supplies.
> 
> Corsair, like Antec and others, used to offer nothing but top-tier PSUs but they have expanded to offer supplies across the board. So do your homework first and consider "investing" in a 80 PLUS Gold certified. Gold certified cost more up front than Bronze (or basic 80 PLUS) but, they offer better regulation and lower ripple when stressed, and lower efficiency ratings (lower is better) which, over the life of the PSU, can result ultimately in lower energy costs.





greenbrucelee said:


> corsair are ok but not greatm they used to be until they started using a low quality manufacturer to make them to save money.
> 
> Seasonic, xfx amd antec hcg are the best


Thanks for these useful and detailed pieces of information. I've been having second thoughts about this power supply (link in previous post). Initially the Corsair name and the 20 dollar rebate lured me in, but I'm old enough to have been here before and now I'm concerned that NewEgg is "getting rid or" what might be defective, or really poor quality PSU's.

I can afford $60 for this computer. It doesn't deserve any more money than that. If it was a higher-end computer I'd spend more on the PSU, but at this point I just need something reliable for internet & email. No gaming, high-CPU intensive computing, video rendering, etc... I'm thinking 450 Watts should be adequate so if anyone has a recommendation for a low-end power supply that I won't have to worry about going TU and killing the hard drive and the data that's on it (my biggest concern), I'd like to look at those recommendations as an alternative to this Corsair that might be a guarantee to problems, due to the deep discount they are offering.

Are bad capacitors still a problem in the industry? Could this be an explanation for why this Corsair is so cheap?


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## Bill_Bright (Dec 17, 2004)

> I'm concerned that NewEgg is "getting rid or" what might be defective, or really poor quality PSU's.


Newegg is a reputable maker that sells products for all budgets. Even a cheap 80 Plus Corsair is miles ahead of any off brand PSU that is not 80 Plus certified. Newegg would not knowingly sell any defective product and when a product is DOA, they have one of the best return policies and reputations in the industry. 



> Are bad capacitors still a problem in the industry?


Not like they used to be when they failed prematurely. But like all products, there are different levels of quality - typically directly related to costs. 

Lessor quality caps today typically mean higher ripple - an unwanted AC component riding the DC voltages. But that does not mean the ripple is high, and definitely not higher than the ATX Form Factor allows. 

Review sites would be unhappy with 60mVpp (60 millivolts peak to peal) ripple on the +12V rail because the best PSUs are less than 30mV. And they would be unhappy with 30mV on the 5 or 3.3V rails. Yet the standard calls for a maximum of 120mVpp on the +12VDC and 50mVpp on 5 and 3.3. 

So a PSU that does come in higher but still well under the maximums does not mean the PSU is bad, or unreliable, or harmful to the rest of your computer.


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## greenbrucelee (Apr 24, 2007)

its not the capacitors it's the fact that corsair started using CWT to make their power supplies instead of using Seasonic and this has lead to a few bad units. Antec did this a few years ago and their sales suffered because of it. Now Antec have learned their lesson although it took them 5 years.

Corsair will learn the same lesson. I have alread had to RMA 2 units myself one of them was DOA. Corsairs RMAs have doubled since they started doing this.

Now let me get this straight CWT so not make crap power supplies its just that their quality is not as good as the makes I have mentioned and therefor things are more prone to go wrong.


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## Bill_Bright (Dec 17, 2004)

> and this has lead to a few bad units.


Key word being "few". Not all CWT supplies are inferior and more importantly only a "few" would be considered "bad" or to be avoided. So regardless, "few" does not indicate "every" model is inferior - and there are plenty reviews at reputable hardware reviews sites to support that.

What I am saying is even BMW makes some models that probably should not bare the BMW brand, but that does not mean BMW should be avoided at all costs. 

Bottom line: do your home and research specific models.


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## greenbrucelee (Apr 24, 2007)

that's why I said CWT do not make crap power supplies but their quality is not as good as the ones I mentioned.


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## Bill_Bright (Dec 17, 2004)

Yeah, I agree. It is actually surprising how few PSU makers there really are. It is not uncommon to see the exact same OEM supply inside several different "branded" cases.


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