Four 80 PLUS Gold Power Supplies Under 450 W, Reviewed

Corsair RM450

Corsair’s description of its RM power supply family is very matter-of-fact. Gold-certified and fully modular are the two phrases used for marketing, and there's not much else to add except maybe that these PSUs are also optimized for quiet operation. After all, Corsair does enable hybrid fan control, meaning the fan stops when temperatures are low enough to support passive cooling. The outcome, of course, is silent operation in those cases (at least, that's how it's supposed to work in theory).

In any case, Corsair's build quality is good and the materials used are excellent. The RM450's matte black finish and rounded edges look nice, though the chassis isn't as compact as Cooler Master's and Seasonic's competing products. All of the bundled cables are modular and flat. As far as cable length and available leads go, Corsair lands in the middle of the pack. Its single +12 V rail is good for up to 37.5 A, according to the company's specifications. As we’ve seen before, the PSU comes with a five-year warranty.

AC Input100-240 V, 47-63 Hz
DC Output+3.3 V+5 V+12 V (#1)+12 V (#2)+12 V (#3)+12 V (#4)-12 V+5 Vsb
24 A22 A37.5 AN/AN/AN/A0.8 A3.0 A
Individual Output      9 W
1 W
Rail UtilizationSysSysCPU & VGA
Combined Output110 W450 W
Total Continuous Output450 W
Peak Outputn/a


A fully modular configuration has the advantage of more flexibility, especially when you need more specialized cables. The flip side of the coin, however, is an efficiency loss. Additional boards, conducting paths, and connectors all have a cumulatively negative impact on this important criteria.

As we might have expected, then, the measurements required for 80 PLUS Gold certification are a close call for the RM450. It manages to hit the three necessary benchmarks with no room to spare whatsoever. Lower loads look worse though, and those are what a normal PC will deal with most of the time. At 50 W, Corsair achieves an efficiency level of 80 percent. This drops all the way to 72 percent at 25 W.

Hold-up time is one of the RM450’s strengths, registering 24 ms. The ripple and noise measurements also speak to this power supply's high quality; they're similar to what we saw from Cooler Master's V450S. We also saw very low power consumption (.04 W) at standby without any load, which is great.

Thus far, Corsair's RM450 looks great. And, due to its dynamic fan control, it should also sail through our acoustic measurements. Then again, we’ve seen power supplies marketed as semi-passive that ended up sounding like hair dryers when their fans spun up.

Fortunately, Corsair's RM450 doesn't disappoint. Under a 200 W load, the fan didn't spin, and after 30 minutes of heat build-up, we were still waiting for it to make noise. We finally triggered the fan at 360 W, and even then it only generated a barely-noticeable 30.4 dB(A).

A Look at the PCB

Corsair has been working with CWT for years, and the RM family is a product of that collaboration. The chassis' build quality is high, similar to everything we find inside.

The input filter is separated into two parts consisting of two X and four Y capacitors, which work in conjunction with a MOV and two choke coils. The primary capacitor is made by Panasonic yet again. We find secondary ones from Nippon Chemi-Con and CapXon, the latter of which seems to be a popular Chinese supplier these days.

Corsair also uses a DC-to-DC converter topology, but skips the LLC and uses a somewhat dated IC instead. Nevertheless, this configuration is good enough to earn that Gold certification. Solder quality is consistent with what you should expect in this price category.

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37 comments
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    Top Comments
  • oczdude8
    Is it just me or is $100 WAY too much for a 450W psu......
    16
  • Other Comments
  • iknowhowtofixit
    No ripple tests, no noise (not sound) tests, and no oscope shots.... *facepalm*

    Readers have been begging for you guys to do a proper PSU test for years. I'm glad to know Tom's has taken the time to listen.

    /sarcasm
    7
  • iam2thecrowe
    they did ripple tests......they load tested them....... that's about as much as most readers need to know, that it wont blow up at 100% load and wont damage components with excess ripple. better than some reviews i have read "we hooked it up to a pc and it worked, give gold award..."
    2
  • Onus
    Too bad Rosewill did not submit its Capstone for this roundup.

    It would have also been nice to see one of Seasonic's TFX units included.
    4
  • iknowhowtofixit
    Anonymous said:
    they did ripple tests......they load tested them....... that's about as much as most readers need to know, that it wont blow up at 100% load and wont damage components with excess ripple. better than some reviews i have read "we hooked it up to a pc and it worked, give gold award..."


    I lol'd at the operational noise graph because it tells you nothing. What rail(s) are they testing? Who knows? Who cares...

    You are welcome to continue to defend the article, but the truth is that nobody takes a Tom's Hardware PSU review seriously. This review doesn't do anything to change that perception. Compared to the depth of analysis that goes into other PC components, it is disappointing to see Tom's continue to ignore the requests of its readers to bring a thorough, full-featured PSU review to the table.
    6
  • xenol
    Ripple and line noise tests are the indicators of whether or not a power supply is made with solid parts or made with parts that just do the job and will probably last about a year of nominal use before releasing the magic smoke. If there's a lot of ripple, then the motherboard's house keeping circuitry is going to do a lot of work to keep stable voltages (especially when a difference of even 0.1V matters).

    Yes, these are supposedly made by top-tier manufacturers, but just because they have a reputation in the past doesn't mean they have a clean slate the entire way through.
    3
  • 2Be_or_Not2Be
    I am just happy that we have some reviews of more reasonable P/S. Most people I know aren't running 1000W+.

    "In order to keep prices within reason, we settled on an 80 PLUS Gold rating as sufficient to meet our second demand."

    I'm also happy with my 80+ Bronze P/S. Frankly, when you're buying smaller output P/S, I really don't know why anyone would need to get a Gold-rated one.
    6
  • oczdude8
    Is it just me or is $100 WAY too much for a 450W psu......
    16
  • Adroid
    Yea I am really confused by the huge price tags here.

    I paid like 70$ for a top of the line 660W seasonic platinum PSU after MIR. Needless to say I was patient and waited for a good deal, but I see high quality 650-750W PSUs for 80$ after MIRs regularly.
    3
  • hannibal
    Well good quality 400W PSU can be better choice than good quality 600W version. If it works within its best efficiency area.
    1
  • Adroid
    Anonymous said:
    Well good quality 400W PSU can be better choice than good quality 600W version. If it works within its best efficiency area.


    True, PSUs typically operate most effeciently at 80% load. I build gaming rigs though, so 400W is always too small.

    I just expected smaller PSUs to be cheaper, that's all.
    0
  • Drejeck
    There's a big mistake in considering 400W insufficient for gaming. I have a 770 phantom, a 750ti from kfa2 for physx, an i7 2600K at 4,4ghz, various neons, a load of fans, 4 SSDs, 2 black faex 2TB, an asus xonar d2x, and still I can't reach over 420W of power consumption in torture tests, measured with the highest end APC Smart (865W UPS). I have a Corsair 850W Gold, which is a Seasonic rebrand. And I'm ashamed I went so much overkill with my PSU.
    This review feels like useless. There's no ripple testing, whatever the second comment user says. Get some review from Guru3D and you'll see.
    Based on words I can't compare with other products on other reviews, so this is quite a fail.
    5
  • Drejeck
    Oh I forgot, I'm building a gaming rig with a PicoPSU 160XT... deal with it
    0
  • Adroid
    Anonymous said:
    Oh I forgot, I'm building a gaming rig with a PicoPSU 160XT... deal with it


    Haha... well I can beat you on your own games from my cell phone.
    0
  • logainofhades
    Anonymous said:
    Is it just me or is $100 WAY too much for a 450W psu......


    I agree. If I am buying a gold rated 450w unit, I am not buying any of these. I will go and get a Capstone 450w for $60.

    http://www.newegg.com/Product/Product.aspx?Item=N82E16817182066
    4
  • Drejeck
    Quote:
    Anonymous said:
    Oh I forgot, I'm building a gaming rig with a PicoPSU 160XT... deal with it


    Haha... well I can beat you on your own games from my cell phone.

    Hahahaha yup, given a micro HDMI port. But I'm speaking of a machine capable of challenging the PS4. My old NES 8 bit is going to be revived with the KFA2 750Ti and an i5S processor. Actually I badly wanted the Broadwell architecture but I can't wait 2015...
    0
  • Onus
    I used an i5-3570K and an overclocked HD7970 to mine last year, and it pulled 312W from its UPS. Under a gaming load, the GPU usage would drop, and the CPU usage would be higher, but I'd be surprised if it needed more than 350W-375W. It happened to have a pair of WD Blacks in a RAID1 also, plus a SSD, but no other bling. A 400W PSU is plenty for a competent gamer.
    4
  • damric
    This is not a Power Supply Review, this is an informercial.

    The three most important things to review on a power supply are regulation, ripple suppression, and hot box stability.

    My suggestion for Patrick is to go look at CRMARIS and Oklahoma Wolf's PSU reviews to see how a real review is done.

    The only way to verify true quality is with hot box torture. That's how you separate the elite PSUs from the turds wrapped in a box.
    4
  • lp231
    Who the heck wants to spend that much on a 450w PSU? With that amount you can get a PSU with a lot more wattage and still have a 80 Plus Gold rating.
    http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010
    http://www.newegg.com/Product/Product.aspx?Item=N82E16817139056
    0
  • damric
    The $90 750W SUPERNOVA G2/Superflower Leadex sets the bar for quality PSUs. If your PSU you costs more than that and is less wattage then it is fail.
    0
  • lp231
    Anonymous said:
    The $90 750W SUPERNOVA G2/Superflower Leadex sets the bar for quality PSUs. If your PSU you costs more than that and is less wattage then it is fail.


    Unless they buy it for the rating and know nothing else about a PSU, but if you checked out the price links to Amazon, no one is that dumb to spend that much on a small wattage PSU. The CM one is sold by some unknown vender with a $44 dollar shipping! Corsair has some reviews, but that's not for the 450w, they're reviews for higher wattage models.
    0