Back to Article

  • piroroadkill - Thursday, April 24, 2014 - link

    Solid enough, but personally I have no love for Channel Well Technology. Reply
  • Streetwind - Friday, April 25, 2014 - link

    Bit of a shortsighted notion... CWT is an OEM, they manufacture in exactly those quality levels that their customers request. If a customer asks for a cheap piece of crap, the OEM will produce them a cheap piece of crap. But if Corsair says that they need a high quality product, CWT builds them a high quality product. PSU production is not rocket science; it's all about how many corners you're willing to cut to drive the price down. Reply
  • dirtyferret - Thursday, April 24, 2014 - link

    I've owned two CWT PSU and 5-6 seasonic OEM units. Maybe I was lucky but I never had any issue with the CWT units I have owned with both working well for 5+ years. I did get an antec (seasonic oem) with a bad coil, my other seasonic PSU never had an issue. Reply
  • tech6 - Thursday, April 24, 2014 - link

    With CPUs and GPUs becoming more efficient there really is a very small market for 1kW PSUs. Even with dedicated mid-range gaming graphics cards, a lot of new PC never exceed 350W. I wish PSU makers would put as much effort into efficient and quiet low wattage products as they do with overkill products like these. Reply
  • 2late2die - Thursday, April 24, 2014 - link

    Well to be fair the entire RM line is geared towards quiet and efficient operation, so if you want that with low wattage just get the 450W unit. Of course 1kW units are geared towards the smaller enthusiast market, always have been and probably will always be. With that being said, if you want to build a powerful system (not necessarily cutting edge, but above mid-range) and keep quiet, then you want the 850W or 1kW unit because of the whole "no fan below 40%" thing. Like you said, many systems, even at load might not reach 40%, which just means that your 1kW unit will always work completely silently, so that's one less fan for you to worry about. Reply
  • Daniel Egger - Thursday, April 24, 2014 - link

    That doesn't make sense. A high output unit will almost always have a higher loss and thus emit more heat. In other words: it's actually easier to produce a fanless 400W unit than to produce a 1000W unit that runs with a fan at 0 RPM below 400W. Reply
  • PEJUman - Thursday, April 24, 2014 - link

    ^^not exactly, you're correct for PSUs from 10 years ago, however the 80 certification requirements forces the modern PSU design to be efficient at all loads:
    the 80 gold requirements: min efficiency @ 20% load = 0.87, 50% load at = 0.9, 100% load = 0.87

    Therefore a 450W 80 Gold will only be 3% (6 Watts) more efficient than a 1000W 80 gold at 200W load.
  • Daniel Egger - Friday, April 25, 2014 - link

    My point is this: If you want to build a system designed for 400W max output it does *not* make sense to use a 1000W just because it happens to run at 0RPM below 40% utilisation.

    BTW: Not sure your what you meant by "you're correct for PSUs from 10 years ago" because your own calculation proves that I'm still correct for current PSUs. 6W are nothing to sneeze especially considering that no decent system has an idle load of 200W, not even an unlocked haswell setup with crossfire r9 295x2 cf. (which this PSU couldn't drive anyway) and those figures are going to be much worse for sane setups.
  • owan - Friday, June 27, 2014 - link

    He didn't say at Idle, he said 200W load. Considering that PSU's are most efficient at 50% load, it actually makes some sense to size your PSU to keep the max load closer to 50% than 100%, particularly if you run your system at high loads for a high percentage of its uptime (i.e. long rendering times, long gaming sessions with minimal other usage) With a high end system drawing well over 500W from the wall, a 1000W PSU is a perfectly sane choice Reply
  • UnknownZA - Thursday, August 20, 2015 - link

    The problem is that new GPU's like Maxw ell do draw more power. A normal 980 GTX Ti apparently only draws 250W which is excellent. However, most if not all of the overclocked 980 GTX Ti's that are on the market draw much more power.

    I have a GALAX 980 GTX Ti HOF and under full load it draws close to 480W.

    I currently have a Corsair TX 750W which I thought was more than enough power for my system, currently Z68 with 2600K, but bought a 4790K and Z97 too. However I have had quite a few crashes while playing games and I have come to the conclusion that the PSU is not suppling enough power. So I am looking at this 1000W Corsair RM. I could go with the 850 but the price difference is negligible.
  • Daniel Egger - Thursday, April 24, 2014 - link

    I think you and I might as well give up as I sense a lot more of those nonsense^Wniche product reviews coming up... Reply
  • mattgmann - Thursday, April 24, 2014 - link

    Your statement is true, except for the mass demand of high wattage PSUs for mining. Many 1k units are constantly sold out at major retailers because of the demand for mining rigs. Reply
  • derpherp - Wednesday, April 30, 2014 - link

    This actually doesn't work that well when I try to use the zoom mod script:
  • Ubercake - Thursday, April 24, 2014 - link

    My TX950 was built by CWT and continues to be a solid performer. I would have no issue buying this PSU at $170. That's a good price for 1000W 80-plus gold supply. Is there anything else close for that price?

    Two standard R9 290xs in crossfire will require 600W+ themselves without an overclock. Even though CPUs seem to be improving with regard to power usage, for souped-up gaming systems, more wattage is still required and GPUs seem to be requiring more power these days.
  • Antronman - Thursday, April 24, 2014 - link

    More like 450ish Reply
  • zlandar - Thursday, April 24, 2014 - link

    Like to see some reviews on small form factor PSUs that can fit into smaller cases. Reply
  • eanazag - Thursday, April 24, 2014 - link

    I agree. Looking for itx case power supplies is not a lot of fun. Also, looking for low wattage PSUs sucks. Solid performers at 350 and below are interesting. Reply
  • meacupla - Saturday, April 26, 2014 - link

    There is the Corsair CS series for that, which is gold and standard 140mm depth.
    But if you want higher quality than CS series, Antec earthwatts platinum is also good.
  • 2late2die - Thursday, April 24, 2014 - link

    Other than the size this looks like a great PSU for any high-end system. By the way, while the marketing for the RM series emphasizes the no-fan operation at low loads, I believe the AX series has the same feature and won't kick in its fan until 40+% loads. Reply
  • Antronman - Thursday, April 24, 2014 - link

    It's too bad that Corsair's RM series are horrible quality. Reply
  • dirtyferret - Thursday, April 24, 2014 - link

    too bad every professional reviewer disagrees with that opinion Reply
  • frewster - Thursday, April 24, 2014 - link

    Thanks for the good laugh. There seems to be an influx of people who believe that any PSU not made by Seasonic is trash, but that's BS. Reply
  • meacupla - Saturday, April 26, 2014 - link

    The fan itself is a cheap sleeve bearing type.

    I don't understand why these companies opt for fans that can't be orientated horizontally without increased wear and noise. And the thing is, the price difference between a sleeve and double ball bearing fan is only about $1
  • benbenkr - Monday, May 12, 2014 - link

    There's one issue these pro reviewers never seem to mention, coil whine. It doesn't inherently make a PSU bad, but boy it is annoying.

    I just replaced a RM650 due to the insane coil whine it has, even at low level loads.

    The CWT made RM Corsair PSUs are quite solid, credit where it is due. But the coil whine is ridiculous. For that, I needed to change to a Seasonic KM3-based platform in the spirit of a Cooler Master (I know, a brand notorious for horrible PSUs) V700.
  • frewster - Thursday, April 24, 2014 - link

    I don't think you know what you're talking about. Those ones made by Chicony? They're on par with Delta quality PSUs. And CWT? Hardly "horrible." Reply
  • YoloPascual - Saturday, April 26, 2014 - link

    Yeah the server psu's that are made by Chicony are on par with Delta. The RM750 and RM850 are not. CWT made HX series are very good. CWT made RM series are mediocre at its finest. I does not need to be Seasonic/Super Flower made, but it should competent. Reply
  • just4U - Thursday, April 24, 2014 - link

    I wish they'd use seasonic more. Reply
  • Voldenuit - Thursday, April 24, 2014 - link

    I have a CWT ODM Corsair CXM-500 in my rig. My beef with it is that while it is pretty quiet at idle, running a GPU load (gaming, video benchmarks) on my GTX 760 will bring the fans up until it becomes the noisiest component in my system.

    Running a pure CPU load (undervolted i5 4670K) such as Prime95 does not elicit this behaviour, and I've controlled for other variables such as case, CPU and GPU fan speeds, so the threshold for "noisiness" from the PSU seems to be around 200-250W, which would correspond to a 40-50% load on the PSU.

    It's not unbearable, and not worth returning or exchanging the unit, but it was a bit disappointing for me since I was trying to build as quiet a system as I could on my budget.
  • Voldenuit - Thursday, April 24, 2014 - link

    PS It's worth noting that I don't have any sound measuring equipment, so I don't have any SPL measurements, and that my personal threshold for noise and my apartment noise floor might be very different from others'.

    I've seen posts both praising and condemning the same CX-500M (sorry, had the model number mixed up in OP), so YMMV.
  • lorribot - Thursday, April 24, 2014 - link

    Does truly have a "chamfered edges and the rimmed bottom" as you state in the conclusion or should that be a ribbed bottom? Reply
  • tynopik - Thursday, April 24, 2014 - link

    where's the cart with cable lengths and connector spacings? Reply
  • poohbear - Thursday, April 24, 2014 - link

    so, in 2014, what kind of system actually needs 1k wts? CPUs and Graphics cards are as power efficient as ever, so what are people doing with these 1k psus? My GTX 670s in SLI pull 300wts together under load, the newer graphics cards are even more power efficient, so what gives? Reply
  • peterfares - Friday, April 25, 2014 - link

    mining coins Reply
  • meacupla - Saturday, April 26, 2014 - link

    You're not supposed to load it up fully, because efficiency drops off.
    Generally, what you want to do is load up the PSU so that it's operating near peak efficiency where the computer is going full tilt. If you run an overclocked i7 and a pair of 780 cards, I think that gets you into the 600W range, or 60% load for this PSU, which is around the peak efficiency for it.
  • Antronman - Saturday, April 26, 2014 - link

    2-way water OC SLI/CF with high-end cards+ CPU OC on water.
    600-700w power draw easily, and then another 80w+ for the monitor, plus 10w for each USB device.
    ba-bam, you need a 1000w PSU.
  • royalcrown - Monday, April 28, 2014 - link

    Except the monitors don't run off the psu ;) Reply
  • tabascosauz - Friday, April 25, 2014 - link

    I had hoped that the higher wattage RMs (850W and now 1000W) would trade CapXon/TAICON/Teapo caps for Chemicon/Rubycon ones and the zero rpm fan profile for an even quieter fan, but I guess one can't always get what he wishes for.

    The thing is, at this price range there's just so much competition. You have absolutely stunning 80+ Gold and Platinum 1KW+ platforms from Super Flower, Seasonic, and Delta that don't miss a beat when it comes to high quality components and impeccable solder jobs. This makes the RM a lot less attractive (well, it does look nice on the outside but most other KW+ units also look nice).
  • YoloPascual - Friday, April 25, 2014 - link

    This psu has a zero rpm mode. The heat will f**k up those capxon and taicon. RM1000w is $190 now in newegg, EVGA G2 1000w $200 , Cooler Master V1000w $210.
    Those who got more than 2 gpus will not bother to expend 10-20$ more if they can a much better psu. IF those people know more, not just brand names.
  • jonnyGURU - Friday, April 25, 2014 - link

    I disagree. Not only are these caps rated at 105°C, but the temperatures inside the PSU don't get anywhere near that. Remember that the life of the cap increases exponentially the cooler it is from it's max rating.

    Also, Japanese caps are quite over-rated. They're not even made in Japan anymore (they're just Japanese brand) and the Chinese are using the same Japanese electrolyte and aluminum that the Japanese brands are using.
  • tabascosauz - Friday, April 25, 2014 - link

    Well, manufacturers can obviously RATE their caps at the temperature they want them to be rated, but not all of them will deliver. Teapo has been in the game for quite a bit of time and now it's pretty much agreed that they are capable of delivering on the same level as the Japanese ones, but it's the TAICON and CapXon ones that are a little less sure.

    I do agree that even with a zero rpm fan mode, there's still a pretty capable fan on the RM. That's the reason why I would never buy a Seasonic fanless PSU for any reason. I must say that I haven't seen many 1000+ units from CWT and don't know how they fare (from the soldering jobs that they do I would say that CWT needs some more experience in the high end market, although it shouldn't really affect performance), Seasonic, Delta and to a certain extent Super Flower can claim their superiority here.

    Are you OklahomaWolf or are you just a fan of jonnyGURU? That site is one of my go-to places for an education on PSUs, aside from TPU. All the others are pretty much junk.
  • khanov - Saturday, April 26, 2014 - link

    You can turn off the fanless mode on Seasonic's PSUs. That'd be a good option for Corsair to adopt I think.

    As for the Teapo comment, surely you cannot be serious. Teapo electrolytics as filters are a terrible option. They rarely last even half their rated lifetime. I replace Teapos quite a lot in consumer electronics devices (TVs, set top boxes, DVRs etc). They seem to go about 5 years on average before they fail with open vents.

    The real problem when you go lower than first tier Japanese is that the manufacturers will sometimes straight up lie on their spec sheets. So they look like they should perform just as well on paper, but they never meet that performance in real applications unless treated much more gently than their specs would suggest. Ripple current (real vs rated) is one area where I see a lot of this happening and Teapo is one of the culprits.
  • YoloPascual - Friday, April 25, 2014 - link

    I know your work for Corsair now jonny. Don't worry many ppl will still buy your incompetent psu because most of the people knows that if a psu has corsair sticker, it must be excellent.
    And no japanese caps are not over-rated actually they are under-rated. I got a Delta made psu from 1999 running like champ. It has a combination of Rubycons and Nippon-Chemicon.
  • royalcrown - Monday, April 28, 2014 - link

    Come on! You act like Corsair sells dog poop. Whether or not you like them, they are not junk either. Calling it incompetent just reeks epeen elitism... Reply
  • just4U - Saturday, April 26, 2014 - link

    What I really dislike about the RM line is they are very close in price to the HX series that was made by seasonic. (A company I trust) I expected these to be made by them.. but nope. Ticks me off.. I like Corsair branded Seasonics.. their the only ones I will buy, period. If Corsair is moving away from them.. then I am moving away from Corsair. Reply
  • Harald - Monday, May 05, 2014 - link

    Actually, there was only ever one HX model made by Seasonic and that was the first revision of the HX650. I have the HX750 which is made by CWT, it's going on 4 and half years old and working like a charm. Reply
  • Harald - Monday, May 05, 2014 - link

    (Sorry, forgot about the HX520 and 620) Reply
  • khanov - Friday, April 25, 2014 - link

    +1 from me too.

    I'd have to skip this and go straight for an all Japanese-capped unit.

    Also, are you sure there aren't any Ltec caps int here? I can't see well enough, but those green filters on the secondary side look suspiciously like the worst caps money can buy.
  • sor - Friday, April 25, 2014 - link

    I didn't see the voltage being tested. usually there's a 2-3% efficiency gain at 220-240V Reply
  • JASTECH - Friday, April 25, 2014 - link

    I have a 1050w modular, don't recall brand, I bought before my surgery then ressesitated, ICU then on O2 24/7. So its been a few years sense my purchase, anyways, out of the box hooked up not working. Tested it, seems a 5vdc not working. Quality PSU is DOA, so QC is still lacking. Reply
  • meacupla - Saturday, April 26, 2014 - link

    YES to ribbon cables. More PSUs should come with this, as it is superior to braided sleeving and individual strands in terms of routing and bundling.

    NO to right angle SATA connectors! The cable lengths end up being wrong anyways and there is extreme strain on the cable where the pins bite into the wire. The cable just doesn't bend as smoothly as daisy-chained straight connectors.
  • ssj3gohan - Monday, April 28, 2014 - link

    Can I give some constructive criticism?

    The review is missing some parts that would be very useful:
    - The teardown is extremely short and basically useless. All the information we get from it is that it's made by CWT. There is a lot more to see that is relevant, like the topology (it's obviously LLC resonant, otherwise the heatsinks for the active devices could never be that small even for a lower powered unit. They dissipate so little because they are switched at zero voltage and current all the time (ZVCS) instead of only half of the time (pseudoresonant) or never (traditional push-pull). Switching losses are the biggest issue in high current PSUs. Another important thing to note is the make of the controller chip(s), as this usually gives a good idea of the modern-ness of the design (LLC resonant has been around for 20 years, but only recently have they really started to do propagation time compensation and such awesomeness). It's also important to note that for instance on this unit, the non-important cap (input filter cap) is from a good brand and the caps that actually matter (high ripple current, high stress in general) are B or C grade. CapXon is not something I would trust handling a couple tens of amps of ripple current for 5 years. Lots of reviewers get fooled by the big shiny cap on the input having the good markings, but this misses the point of cap quality inspection. There's more that should be in the teardown, but for that I'd just recommend aping Jonnyguru, X-bit labs or such people.
    - On the hot *and* cold tests (as well as crossload), at least include a table of the actually used loads and results in numbers, as well as your total (un)calibrated error - depending on whether all your instruments are calibrated or not.
    - Don't fucking interpolate to get nice graphs! This is a deathly sin in data processing. It causes all kinds of crazy things, like implying that the slope of the efficiency graphs is a certain value at the edges (while it probably is something completely else) and causing the weird ripples in the efficiency curve you see. I'd bet money that that ripply stuff is just measurement error. In fact, the entire graphs are a big departure from both the 80 Plus test report and other review sites, so even if this is not actually an error on your part, we need to be able to properly compare this (with table values) to be sure. Even just the sentence 'this PSU was tested on 230VAC input while most other sites test at 115VAC input; this may inflate efficiency numbers' would greatly improve the review.
    - This leads to the next point: interpret the data for us, give us a well-researched explanation for weirdness. Why do the SPL numbers look the way they look? Did you have a tachometer? Did the sound have a broad spectrum or was it whiny?
    - Also: another case of interpolation causing weird graphs is the heatsink temperature graph. Cut that graph in the middle, and annotate it on the left with 'fan off' and on the right with 'fan on'. Don't try to connect the two separate domains, it is meaningless and just causes weird bumps in the graph that are not there!
    - In the conclusion, don't just give a conclusion on this unit in a vacuum. You're a review site! You are supposed to know the market, know the competition. Tell us how the unit performs compared to the competition and how well it is priced. THEN give us a recommendation. Take into account the industry standing of the brand and previous PSUs. As it stands, the conclusion is not satisfactory.

    I'm not trying to be harsh, but Anandtech has a good reputation and there are too few good PSU reviewers around on the internet. You're one of only 3 semi-fulltime PSU reviewers with a master's and/or PhD in the right area, so I have high hopes for the future. I already had high hopes when you were introduced for the first time, but the reviews so far have been passable instead of great. This needs to be fixed.
  • Michal Daniel - Wednesday, April 30, 2014 - link

    Makes for a splendid hackintosh. Typing this on it.
  • amazingrugs - Friday, May 09, 2014 - link

    I've been out of the building game for quite a while. I think the last system I built had a Radeon 9500, when AGP was all the rage! What kind of system does it take to push a PSU like this? Reply
  • alostpacket - Thursday, May 15, 2014 - link

    You guys should never post after-rebate prices, you are doing their marketing for them. Reply
  • burningisis - Monday, November 16, 2015 - link

    I think another use for a high wattage PSU like this other than mining or those using autocad... future proofing a machine. I know I've replaced enough PSUs on my machines as I upgrade GPUs or upgrade the number of drives I use or if I decide to push overclocking. I know some users are going smaller but there are users still out there demanding larger PSUs, running 3+ GPUs, running multiple processors on an enthusiast system. It may be a small subset of users, but there is a demand out there for these, and this looks like a very nice PSU to future proof a build as well Reply

Log in

Don't have an account? Sign up now