Before i begin i would like to state this is not a bash or hate thread of any kind, if you want to take it that way and be personal then please dont bother reading this thread, any and all personal attacks will be reported for breaking OCN terms of service.
Last anyone that does not read the OP and just read title of the thread you got no right to complain and anyone that does will be ignored, if you cant keep it civil you will simply be reported and blocked if you cant follow OCN terms of service.
You have been warned.
Terms Of Service
Alright time to talk about the CX (yet again!) but this time its about the CX750(M) as they are different from the other CX units.
Link to the old CX thread
Why you should not buy a Corsair CX
All of the info and pictures in this thread comes from jonnyguru and hardocp so all credit goes to them as they are the ones that have done all the work and testing.
If you have an CX its not going to blow up or kill your PC, but it has some flaws about it which is what i will talk about in this thread.
Note that all ripple and voltage results are from the unit(s) at full load
Quotes and pictures from the jonnyguru review (Click to show)
Link to the review
Guys, this thing is only rated to full power at thirty degrees. I've spoken about this kind of thing before, but not for a while, so here's my position on this: I have no use for anything that can't do full power at forty degrees or better, and I review these units accordingly. Computer cases routinely see temperatures higher than thirty at the power supply intake, and this becomes more and more of an issue the further south you live, depending on whether or not you're buying this budget unit so you can afford to run the AC.
It also becomes more of an issue depending on where your unit is located. I have family with computers next to heating vents, because that's the only place available to put them. Guess what that does to a Canadian computer? Most of their cases don't have the newer layout where the power supply pulls room temperature air in from underneath the case, so those power supplies are taking in air heated by the vent and the computer hardware. Thirty degrees? Ha!
No, folks, thirty degrees just doesn't work for me. A unit this heavily de-rated is likely only good for 650W at a more reasonable forty to fifty degrees. It may be a perfectly decent little unit, but my hot box will not stay cool enough to make this unit happy. This is by design - my methodology is to get these things to at least forty whenever possible, because that's the lowest temperature I personally expect to get full power out of a unit. Forty is more than reasonable, even for a good budget unit.
Really, here's what it comes down to... this unit has to pass hot box testing, or there will be scoring repercussions on page six. I haven't had to use those particular scoring rules in a looooong time. Corsair, I hope you had CWT give you overtemp protection, because I think this unit is going to need it.
While CWT has in the past given us some excellent soldering work, this was clearly one of their off days. Some of these joints are abysmal, with the PFC parts in particular showing signs of ring cracks.
Seriously? What looks to be a fragment of the exterior finish of this unit is wrapped around the mainboard. Good thing it's non conductive. Even so, I'm going to need to deduct for that. CWT needs to go have a talk with the quality control guys for sure on this one. At least the solder joints in this area of the board look good, except the one near the upper right with too much solder.
More Capxon. Meh. Not terrible, just... meh.
Man, look at that massive solder blob hanging off the red wire lands. This is why CWT isn't on top of the world for build quality yet.
The modular board uses polymer caps from Enesol and Dura Tech. No complaints here. Wait... sigh. See that orange wire between the modular connectors? Here, let me get a dental pick.
It's abraded down to bare wire, right there. There's a ground wire that looks gnawed on, too. That'll be another scoring hit, though fortunately this is the vsense wire for the 3.3V rail and these two are not really in a position to short out on anything. I could de-solder and heatshrink them, but I'll leave them be. They aren't going anywhere.
Once again, I'm not calling the regulation mediocre because the regulation actually was mediocre. It was still in the very good bracket at all times. It did 1.8%, 1.4%, and 1.5%, based on readings of 3.25V, 4.98V, and 11.89V in test five; so it darn near pulled itself into the excellent bracket. It's just that back in the day I felt I needed a way to score an overtemp shutdown without doing any of the special deductions that indicate a unit actually failed in some major rig destroying way, and that seemed as good a way as any.
That said, this unit will still get the half point needed for the efficiency side of things, because right up until it shut down it was still easily doing Bronze numbers. My worst test five power reading was 910 watts on the nose, giving me a result of 81.8%. Adding my usual 1% allowance for test equipment error margins, this unit does get the pass. The only way I would still pull the half point here is if the unit dropped under 81%, or if it had not even started test five. So, Corsair can breathe a sigh of relief on that one.
Let's take a look at some scope shots.
The good news here is that the minor rails are within excellent scoring here at all times, though there is an odd ripple spike or two. They did between 15-20mV at all times, which is really good to see on budget units. The 12V rail, thanks to some odd ripple spikes, did between 25-30mV at all times. Still close enough to call excellent, but I really dislike seeing those oddball spikes in my waveforms. Even so, excellent is excellent. We can't really fault Corsair on these results.
Page 6 - Scoring
Performance (40% of the final score) - and so we come to the scoring. This unit had some good stuff and some not so good stuff to talk about in this category. Ripple control was outstanding, holding excellent results at all times. No deduction will be made there. From there, we'll go dance around the elephant in the room. I call him "Lardbutt," and if you see anyone from the zoo around here you ain't seen nothin.' But seriously, we do have to score the voltage regulation now. Normally, this unit would have only gotten a half point deduction there because of the near excellent numbers I got in the hot box. But... this unit shut down in the hot box, dropping all outputs to zero. That means an automatic slide into the mediocre scoring bracket, which is a full two point deduction, the most deduction possible for load regulation issues under my current methodology. Sorry, Corsair, but I really need your power supplies to finish the hot box testing if you want them to do well. That said, efficiency gets a pass from me on both cold and hot tests, because it held up to Bronze numbers at every turn. Therefore, the performance score today will be an 8.
Functionality (20% of the final score) - there aren't many deductions to make here. The unit isn't fully modular, so half a point comes off there. We have some awful Berg connectors to bother with, so half a point there, too. Mustn't forget half a point for documentation. But I'm going to stop there because everything else is perfectly ok. We didn't get too many hardwired cables, the goody bag came with a decent amount of extra stuff for a value unit, the power cord was nice and sturdy, and this unit has more than enough connectors to get the job done. 8.5.
Value (20% of the final score) - $89.99 is what Newegg's got this listed at. Having made no secret about what I think about units not rated to at least forty degrees, and with clear evidence that this unit does not like forty degrees at full power, I really have no choice here but to compare this unit with 650-750 watt units that can handle some heat. Rosewill in particular has a number of units for the same price or much cheaper right in that power range rated to at least forty degrees. Not all of them are going to give you the same power quality, mind you, but the level of competition is staggering. Really though, it's the likes of the Thermaltake TPD-0750M that spells disaster for this unit, because that one is also semi-modular, good for forty degrees, and 80 Plus Gold for the same price. I recently tested the 850W version of that unit, and it was pretty darn good. Game over, Corsair. Even so, this is a perfectly good unit, it's just playing at a level it can't quite handle. So, I'll go with an average looking 5 here.
Build Quality (20% of the final score) - CWT really had an off day on this one, didn't they? The whole point for soldering comes off today, for some dreadful work to a level I don't usually see from them. Another point comes off for that big flake of whatever the heck it was on the PCB. Another point for sleeve bearings in the fan. Half a point comes off for second tier capacitors. Finally, half a point for the damaged wires. 6.
Build Quality 6
Total Score 7.1
What we have here today, for most of us enthusiasts, is a decent performing 650 watt unit with a 750 watt number on the side. But this unit is not targeted at us enthusiasts, it's aimed at the budget crowd. For those folks, it's a perfectly decent unit and better quality than most of the units it competes against. And let's be honest - you can get the full 750 watts out of it over the long haul if you're careful about thermal management. However, the competition in the 650-750 watt market is so strong that Corsair just can't quite hold on to the ball this time. They almost pull it off, even with all that Rosewill competition, and the presence of a rebate definitely helps, but that Thermaltake... man. That bad boy is a problem that just rips the power cord right out of this unit's hands and whups it with it.
I honestly think you're better off as a consumer if you skip this one and go up another ten bucks to the CS series. Those units actually have a chance against that Thermaltake, are similarly marketed and rated, and they're not too much more cash. I've actually got a CS850M here for load testing... give me three weeks or so, and we'll see how that one comes out. I liked my CS550M enough to keep using it, so I'm hoping for more of the same with some extra power. But this unit? I'd pass. It's not bad at all, in fact it's very good for what it is... it's just not that competitive at this point in time.
very good voltage regulation
excellent ripple control
some CWT build quality blunders
doesn't like heat
a few so-so capacitors
Quotes and pictures from hardocp (Click to show)
Link to the review
Once we open the new CWT built CX750, we see that we are looking at the CWT PUQ-B platform with a double forward primary and a secondary that uses synchronous rectification paired with DC-DC VRMs. From the top, we see that the unit has a total of four heatsinks of various shapes and designs. These heatsinks are paired with a sleeve bearing Yate Loon fan rated at 0.7A at 12v, not exactly the best quality.
Moving over to the secondary side, we see that there aren't any heatsinks here which is a bit odd as the unit was not heavily sinked to the housing via the main PCB either. As before when we have seen this design choice, we don't like this choice at all. We see, just in front of this PCB, a large coil and a smattering of low quality CapXon capacitors. Then, strangely, the DC-DC VRMs have been mounted on its own PCB but rather than attach it to the main PCB it is attached to the housing and this is not a modular unit. Why? This is just a dumb idea since you are going to have capacitors on the side that are trapped against the housing where these are going to get no airflow and Corsair didn't HAVE to to do this. You could however argue the design for a modular unit. The only upside is that at least these are solid capacitors from Enesol (though the PCB was screened for one more than is present) that are trapped. The other small bit of good news here is the soldering is well done on this PCB.
The Bottom Line
The Corsair CX750 is an entry level product from Corsair and, today, it performs a good bit below even those standards given that Corsair used to produce quality products from top to bottom. This unit’s current product placement is readily apparent from the outset as the build quality has issues, particularly noticeable since these are coming from a "name brand" and not a "no name" company. The 3 year warranty support is probably trying to tell us something as well. The unit is not very quiet, and the performance just falls flat as it can not complete testing.
Sure, someone will point out that this is an entry level product and we are reviewing it like it was a "quality" product. Fair enough, but we did the same thing recently to the Rosewill Capstone 750W and that unit thrived, so entry level priced units can indeed be quality units and that is truly what users want. On top of that, for the current $89.99 you pay for this unit you can get that Rosewill Capstone 750W with money to spare, you can get the FSP Raider 750W (not a good choice but it is a better choice than this), and you can get Antec TP-750C today for $54.99 after $30 MIR.
The bottom line is simply this; there is absolutely no reason ANY user should buy a Corsair CX750 as you can get better performing, better built, and better supported products for about the same price or even for much less money. That is unfortunate since Corsair has such a dominate position in etail and retail and users are snapping up lots of these kinds of products based on the name brand only to end up with a product less capable than other options.
One last thing i would like to point out which many are not even aware of as jonnyguru said in his review, the CX series is not designed to operate in temperatures above 30c which is flat out pathetic when most units are designed to operate at 40-50c and higher.
Its pretty much lower then almost everything else on the market.
There you have it jonnyguru has given the CX750 one of the lowest scores in a very long time and hardocp flat out failed it.
Is it the worst unit ever made and is it going to blow up? no but its not all that great either and should be avoided if you looking to buy a 750 watt PSU.