Corsair CX Myths Debunked

[turkey3_scratch]

The Corsair CX lineup is a source of major hate on this forum. Is it a high quality power supply? No. Is it an utter piece of crap? No. The first thing to realize is that the different wattage Corsair CX power supplies have different quality. The Corsair CX 430W is actually not bad, whereas the higher-wattage models are the lesser quality of the bunch. Anyways, to the debunking!

 

Corsair CX Explodes a Lot

 

Any power supply theoretically can explode. Power supplies have fuses which can blow, capacitors which can vaporize and blow, and all sorts of complex components that can emit smoke. But even the highest quality power supplies can explode. Even a G2 or P2 can explode, as happened to a user on Reddit https://www.reddit.com/r/buildapc/comments/3fkjyz/troubleshooting_psu_literally_exploded/ But there is no proof of the Corsair CX being prone to explosion more than any other units. These units sell like hot cakes, and there are only a few I see online that have exploded. If you find the Amazon review page for an actual crap unit, you'll find about 20 1 star reviews saying the power supply exploded. That is not this power supply.

 

Corsair CX Has Bad Voltage Regulation

 

Does it? Let's first take a look at the CX 430, the best of the bunch. The ATX specification says 12V rail outputs must be between 11.4V and 12.6V. 5V rail outputs must be between 4.75V and 5.25V. And 3.3V rail outputs must be from 3.14V to 3.47V. Corsair CX 430 is within these specs perfectly fine. In Jonnyguru's hot box testing, for progressive load tests (equal strain on all rails) the 12V rail output ranged from 11.82V to 11.95V. That is very good. It is all within ATX spec and is arguably good voltage regulation. That is 1.5% off 12V whereas the spec allows 5% offset above and below 12V. 5V rail ranges from 4.99V to 5.10, also very good. 3.3V rail ranges from 3.25V to 3.31V. That is okay.

 

Now, while the progressive load is good, crossload is not. Crossload tests are done by putting a ton of strain on only one rail and having miniscule strain on the other, and testing the voltage of the other. In this instance, the 3.3V and 5V rails were strained to 14A with the 12V strained to only 1A. Visa versa was tested, too. Unfortunately, the 5V rail actually went out of the ATX spec and below 4.75V. The 12V almost did, while the 3.3V rail was good. So, this means this unit sucks, right? Nope. For one thing, it is very rare for crossload like this to ever occur. When on earth are your 3.3V and 5V rails going to be stressed to such extent while the 12V has no load practically? Crossload is very rare, so even if it occurs within a short period of time, the effects will be minimal. As for the 12V rail having load and little on the 3.3V and 5V, sure it can happen, but arguable the 12V rail does power more critical components, and the 3.3V was actually good.

 

Let's look at the CX 750M. I'll make this one quick. Voltage regulation is very good, I'll go as far as great, that is until you start pulling too many amps. At that point, over temperature protection shut down the power supply on Johnny's tests, so he did not get to test crossload either. So is this something to worry about? Not necessarily. I highly doubt anyone is actually running a build that will draw in 750W on this power supply and lives in a hot environment. If your room is super hot and you draw in around 600W of power, the CX750M may shut down due to over temperature protection. But that is a good thing. Corsair is ensuring the unit protects itself by shutting down if it gets too hot. In this particular test, Johnny had room temperature at 42C, which is extremely hot. In the cold tests, the power supply did manage to draw 750W and also had great voltage regulation again. Overall, Corsair CX power supplies have solid voltage regulation, though crossload is questionable.

 

Corsair CX Has Bad Ripple

 

Actually it is quite the opposite. The CX 430 has probably the best ripple in any cheap power supply. The ATX specs says ripple must be within 120mV for the 12V rail and 50mV for the 3.3V and 5V rails. Okay, let's see. Corsair CX 430 has about 15-20mV on the 12V rail in its worst context. That is darn good. See the graph.

The 3.3V and 5V ripple are also very good. Corsair CX 750M has descent ripple. Here is the 12V rail.

The 750M is around 50mV, so well within spec, but not quite as good as the 430W but good for a budget unit. So overall, Corsair CX has good to great ripple!

 

Corsair CX Can't Operate past 30C

 

The power supply is rated for 30C. What does this mean? It does not mean that this unit cannot operate at temperatures higher than 30C. This is just a guarantee stating that this power supply will be able to deliver it's specified amperage on the rails and overall wattage up to 30C. Transistors have derating properties, so as they get hotter, they lose the ability to transfer as much current. So if a power supply is hot, it lowers the maximum amperage it can output. According to expert Gabriel Torres, founder of Hardwaresecrets, the Capxon capacitors in the CX range from 85C to 105C in terms of their operating temperatures. I've seen worse, I've seen plenty of 80C rated capacitors. In johnnyguru's tests, the power supply actually managed to operate fine exhausting temperatures at a staggering 62C. Keep in mind this is exhaust, so it is heat dissipated. It's the heat that is actually gone from the power supply, but chances are the unit itself was past 50C and working fine.

 

Corsair CX Uses Capxon 

 

Yes it does. But did you know CX power supplies also use Teapo ones? (not that they're really any better). So it uses Chinese capacitors. So yes, they are bad capacitors, but in a build that does not strain these power supplies to their potential, the capacitors should last perfectly fine a few years. They are what they are, and they happen to do one heck of a job with the ripple suppression, just as the inline Capxon capacitors on the EVGA G2 also do.

[BrinkGG]

[removed]

Mind if I link this in my sig?

Edited December 17, 2015 by Godlygamer23

[AresKrieger]

I'm not even going to read this, regardless the CX line are bad PSUs, not the worst by any means but doesn't met up to my standards, which means I WILL NOT RECOMMEND IT!!! The same goes for any of the other PSUs in the meh category of the list in my sig.

[Fulgrim]

I still prefer Seasonic/SuperFlower units over Corsair nowadays.

[turkey3_scratch]

I don't recommend them either, I recommend higher-end power supplies with Japanese capacitors, but I just wanted to show that these aren't awful. Honestly, if these did have Japanese capacitors, I would recommend these out the wazoo! But the other non-capacitor aspects of the power supply are quite good.

[techguru]

the point of telling people who have a cx psu in there builds isn't that cx are the worst pieces of garbage out there

 

the point is that there are much better quality psu's for not much more or even the same

[turkey3_scratch]

the point of telling people who have a cx psu in there builds isn't that cx are the worst pieces of garbage out there

 

the point is that there are much better quality psu's for not much more or even the same

Yes there are. That is the same reason I don't ever recommend Corsair RMx or RMi units. EVGA G2 and GS are just such better value. The higher-wattage Corsair power supplies are overpriced. The CX 430W however can be found extremely cheap and is not bad for an office build.

[typographie]

I still prefer Seasonic/SuperFlower units over Corsair nowadays.

 

Well, who wouldn't prefer a Ferrari to a Chevrolet? The CX series aren't really intended to be compelling to someone who has $80-100 to spend on a PSU. They actually don't have a lot of respectable competition at the prices they go for, except maybe EVGA's NEX products, and I don't think they're much better.

[STRMfrmXMN]

Yo I did have a guide to them awhile back and it's in my sig

[turkey3_scratch]

I think we all agree they are for low-power builds with either very weak or no GPU.

[UL_42L]

I'm not even going to read this, regardless the CX line are bad PSUs, not the worst by any means but doesn't met up to my standards, which means I WILL NOT RECOMMEND IT!!! The same goes for any of the other PSUs in the meh category of the list in my sig.

Should you really be commenting on something you didn't read?

[AresKrieger]

Should you really be commenting on something you didn't read?

I already know the argument, the way it is written here is too long winded for me to care (aka tldr), besides I already know the key points.

[Patrick Bateman]

TLDR pls 

[CalebTheEternal]

Doubt anyone will have the issue of the cx750 shutting down? I had that. Then again I was using a good system on a cheap PSU. My room was also hot. My PC would shut off sometimes 3-4 times a day. This is why I don't recommend CX power supplies.

[UL_42L]

I already know the argument, the way it is written here is too long winded for me to care (aka tldr), besides I already know the key points.

In my honest opinion, TL;DR is (to put it as politely as I can) for those who shouldn't be on a forum... they have many long posts.

[TheMidnightNarwhal]

I still prefer Seasonic/SuperFlower units over Corsair nowadays.

 

Some Corsair PSU are Seasonic...

[turkey3_scratch]

Doubt anyone will have the issue of the cx750 shutting down? I had that. Then again I was using a good system on a cheap PSU. My room was also hot. My PC would shut off sometimes 3-4 times a day. This is why I don't recommend CX power supplies.

And that perfectly matches the explanation I had in the original post. I said the 750 will shut down if in a hot room, and that I'd only recommend not running components that get near 600W.

[Guest]

Oh man, nice. Had a CX before my EVGA and I still stand by my CX, there is nothing wrong with them and the hate is extremely over exxaggerated.

[don_svetlio]

Office PC? Sure, CX for 15$ all the way
A system with a OCed R9 380/GTX 960 + i5? Bad idea

[hug0mac]

It's not a bad PSU for basic builds OMG... it's just not the way to go wtih high end....

 

 

that is what should be debunked! 

[Corsair Joseph]

This says it all! Informative and has all the factual data that you need to know about the CX. It's definitely worth reading, Thanks for taking the time to put this together, such effort 

[turkey3_scratch]

This says it all! Informative and has all the factual data that you need to know about the CX. It's definitely worth reading, Thanks for taking the time to put this together, such effort 

No problem!

[Swndlr]

Some Corsair PSU are Seasonic...

Yeh My HX650 is made by SeaSonic.

[V-e-l-o-c-i-t-y]

I think we all agree they are for low-power builds with either very weak or no GPU.

So you're say my cx 500 might f**k me over?!

I have a 960 4gb!?

[Guest]

On 12/26/2015 at 0:47 PM, V-e-l-o-c-i-t-y said:

So you're say my cx 500 might f**k me over?!

I have a 960 4gb!?

Nah itll be fine.