SPCR

Corsair CX400W Power Supply - first article by new SPCR reviewer Mike Vass

Looks like reliable PSU for my home server, and I probably won't hear it over Antec 300 stock fans and Two more TriCool's

Great review!

The Corsair is even better when it is found on sale at Fry's for $29.00.

I just put one in my parents' PC. The first thing my mom said was "If it didn't have the light on the front, I wouldn't know it was on!"

-D

I bought one of these a year ago from Newegg for $20 with free shipping.

Thanks for the review. Knowing how this budget PSU performs is great.

One thing though - I've noticed that some recent SPCR PSU reviews, including this one, haven't included fan voltage at particular loads in the Test Results tables.

The last PSU review I found with this data was the Seasonic M12D-850W review.

I'm just wondering if there were any technical reasons for this data not being gathered or included?

For budget PSUs, a fan swap isn't out of the question, so having data on the fan voltages at particular load levels is useful, at least to my mind. I've used this data and combined it with the dBA ratings of fans from SPCR's fan reviews in the past to estimate how a fan swap on a PSU would make it quieter. (This method worked great for guessing how swapping an S-Flex 1600rpm into my Zalman ZM600 PSU would work).

Any chance of this data being included in PSU reviews again?

Bit noisy at low load and more noisy at high load

Noise from ADDA fan on this PSU was so annoying. Mine become much quiter after did some fan swap

JamieG wrote:Thanks for the review. Knowing how this budget PSU performs is great.

One thing though - I've noticed that some recent SPCR PSU reviews, including this one, haven't included fan voltage at particular loads in the Test Results tables.

The last PSU review I found with this data was the Seasonic M12D-850W review.

The fan voltage data is included normally, but there have been a few cases where it was simply not possible for odd technical reasons -- odd meaning we couldn't figure it out and there often isn't enough time (or benefit) in finding a way. The most common reason for not being able to measure fan voltage these days is PWM fan control -- it's becoming much more common. This may force us to install some kind of strobe or other optical fan speed monitoring device inside the PSU test box -- facing up to the spinning fan.

With regard to the fan voltage on this Corsair, we erred. The new reviewer and I had our wires crossed, and the data was simply missed. It's just been put where it's supposed to go -- in the "Other Data Summary table" -- and the accompanying text corrected.

My take on this Corsair is that for the typical minimalist SPCR system, it'll be nicely quiet, though not silent -- which is what you might want if you've gone to an SSD or a super quiet HDD that's suspended/enclosed. I mean take a look at the AC system power figures for the last AMD785G motherboard review. With a 95W TDP X3 X3 720, those systems drw just 30~40W AC at idle and didn't even reach 120W AC at the ultrapeaks. OK, add a mid-level video card and you might reach 200W AC peaks. Might. In a decent case set up intelligently, this PSU still won't ramp up.

And its electrical performance is really really good.

MikeC wrote:With regard to the fan voltage on this Corsair, we erred. The new reviewer and I had our wires crossed, and the data was simply missed. It's just been put where it's supposed to go -- in the "Other Data Summary table" -- and the accompanying text corrected.

Awesome. Thanks Mike.

For all the talk about the low power requirements for the majority (which I agree with), SPCR have very few reviews of PSUs in the 400w range. Particularly the available every where Antec Earthwatts like the new 380/430 models.

MikeC wrote:In a decent case set up intelligently, this PSU still won't ramp up.

And its electrical performance is really really good.

Valid points, but the CX-400 remains in a tricky spot. Spending a little more definitely can buy a quieter PSU. With the CX cheap only during MIR specials, bargain shoppers will consider other models & fan swaps. Not a lot of room in the middle for Corsair.

How about reviewing the Seasonic SS-300ET? It appears to be the modern Super Tornado and ought to be very competitive in this segment.

b_rubenstein wrote:For all the talk about the low power requirements for the majority (which I agree with), SPCR have very few reviews of PSUs in the 400w range. Particularly the available every where Antec Earthwatts like the new 380/430 models.

The EA430 was reviewed here 3 years ago. http://www.silentpcreview.com/article684-page1.html
I don't believe it has changed significantly; Antec would have told me if it had. Basic 80+ rating.

Other lower power PSU reviews --
Seasonic M12II-430
Nexus Value 430 PSU
Winmate DD-24AX DC-DC Module for Silent, Efficient Power (130W)
Sparkle Power's 250W ATX12V 80 Plus SPI250EP
Seasonic Eco Power 300
Sparkle Power SPI220LE 80 Plus FlexATX PSU
Seasonic S12II-380
Corsair VX450W

I bet this list is twice as long as that of any other PSU review site. Keep in mind that in the last few years there has been very little real activity or development of new models in the <400W range. Most good name brands begin around 400W and go up.

Ah -- just saw what b_rubenstein might have been referring to at the Antec website -- a new Earthwatts 380D Green. 80+ Bronze, so higher eff. and no power cord -reuse your old one. This is worth a visit, will see if we can get 380/430 models to review. I wonder when it was introduced...

The older Earthwatt 380/430's were OEM'd by Seasonic and the new ones are made by Delta. They're important, because they are sold in so many places and come in a number Antec cases.

b_rubenstein wrote:The older Earthwatt 380/430's were OEM'd by Seasonic and the new ones are made by Delta. They're important, because they are sold in so many places and come in a number Antec cases.

You could be right. We'll get samples of all 4 models.

Glad to hear that you'll review Earthwatts series, MikeC. Still, some people claimed they were quiet. But we would like to have SPCR's official approval or disapproval as Antec had changed OEM source of its Earthwatts series a year ago,

As for Seasonic, I doubt whether they were interested in providing mid/low-end offerings or not given the non-existent S12II Bronze reviews on the Internet.

MikeC wrote:...The most common reason for not being able to measure fan voltage these days is PWM fan control...

The easiest way around that would be to buy a multimeter that can measure duty cycle, which will show you the fan speed directly as 0-100%.

Mr Evil wrote:

MikeC wrote:...The most common reason for not being able to measure fan voltage these days is PWM fan control...

The easiest way around that would be to buy a multimeter that can measure duty cycle, which will show you the fan speed directly as 0-100%.

Or just stick an oscilloscope on the PWM pin and see what's going on.

HammerSandwich wrote:...How about reviewing the Seasonic SS-300ET? It appears to be the modern Super Tornado and ought to be very competitive in this segment.

I picked up the 350ET as the 300ET wasn't in stock at that time. It's been great but the medium speed ADDA fan had some brushing/clicking type noise. I swapped it for a low speed ADDA fan but I think it actually has more brushing/clicking going on even if it does spin a little slower. My PC is pretty quiet so when the heat isn't running or anything else in the house making too much noise, it's definitely noticeable. Need to swap it for a better fan still. Also, since it's an OEM, I needed extension cables in my mini-P180. I'd definitely buy more of these. But for the mini-P180, I'd probably go with the S12II 330 for the extra cable length. Although if the new EarthWatts turn out good enough, those might be an option too.

HammerSandwich wrote:Valid points, but the CX-400 remains in a tricky spot. Spending a little more definitely can buy a quieter PSU. With the CX cheap only during MIR specials, bargain shoppers will consider other models & fan swaps. Not a lot of room in the middle for Corsair.

With its electrical performance backing it up, it makes a great $30-40 power supply, but you are right: At higher cost it seems to fall prey to a myriad of other competitors. Congrats to everyone who snagged it for under $30!

Thanks everyone for the feedback! Sorry about the voltage information; as Mike said, there was a miscommunication on that note. That blip aside, I hope that my future work with Mike proves useful to everyone as well!

I picked this one up awhile ago for $30CAD.... I actually haven't used it yet, but it sounds good as it'll most likely fall under then noise floor with my system.

First a comment on the price vs competitors issue:
A couple of dollars more will either get you a more powerful PSU with a fan setting that produce less noise or a more quiet fan to replace the one inside this PSU.
The advantages of the former option is that it won't void any warranties, and the PSU will support more computer upgrades.
The advantage of the second option is that it is likely to provide better power efficiency for a low power system. If your system peaks at <150W and most of the time operates in the vicinity of idle you want as much power efficiency as possible in this region.

Second a comment about the concept of MTBF:
I too made the mistake of thinking that MTBF was some value of expected life time... it's not!
Somewhat simplified MTBF can be explained as the inverse to the failure rate of a large number of specimens under normal operating conditions. These failures exclude typical fabrication faults (warranty issues) and failures due to old components.
MTBF is mostly meaningful to those managing/supporting thousands of computers, where it gives an indication of how many faults to expect during year two and three of operation. (In year one most failures are from bad manufacturing, and by year four you can expect some failures due to ageing problems.)
So with a 100,000h MTBF you can expect one out of six computers running 24/7 to have a failure during these two years of operation.

Cheers
Olle

BillyBuerger wrote:I picked up the 350ET as the 300ET wasn't in stock at that time. It's been great...

Thanks for the info.

wow. its an earthwatts 380 with black heatsinks.

beware that ridiculous U-shaped piece of plastic on one of the inductors...I had to strap mine in, and while cover was off,as the fans slow to nil (less than 1000rpm) I hacked in a reporting pair of wires from a real fan.

other than that, it is a nice one. no snappy power changes, and calms to next to nothing. I am going four 4hdds in my own system with a 103w prescott, all memory filled, and a 725mhz vid card... (I have the pc in another thread) here.

somebodys 380w is someone else 1000w apparently...