Five Highly Efficient Power Supplies: 1200 W and Up

Seasonic Platinum-1200

We could not help but notice that the top model from Seasonic is almost identical to the Cooler Master V1200, which is not surprising since Seasonic manufactures both of them. Their technical specs are all but identical, and the internal layout proves that these two PSUs are twins. But there are minor differences: The number of connectors, cable lengths, and the fan switch’s labels, where we prefer Seasonic’s scheme (‘Hybrid’ and ‘Normal’) over Cooler Master’s. The Seasonic PSU has two SATA connectors more, but two PCIe connectors less and four Molex connectors less. Except from the motherboard cable, all cables are flat ones, and their lengths are similar to Cooler Master’s cables. Like the Cooler Master PSU there is a single 12 V rail which can supply up to 100 A.

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AC Input100-240V, 50-60 Hz
DC Output+3.3V+5V+12V (#1)+12V (#2)+12V (#3)+12V (#4)-12V+5Vsb
25 A25 A100 An/an/an/a0.5 A3 A
Individual OutputRow 2 - Cell 1 Row 2 - Cell 2 Row 2 - Cell 3 Row 2 - Cell 4 Row 2 - Cell 5 6 W15 W
Rail UtilizationSysSysCPU & VGA
Combined Output125 W1200 W
Total Continuous Output1200 W
Peak Outputn/a

Efficiency According to the 80 PLUS Spec

Efficiency for Typical Use Cases

As expected, the similarities of the Seasonic and Cooler Master PSUs extend to the lab test. The minor differences which did show up can be attributed to parts and measurement tolerances. The Platinum-1200 rightfully bears its 80 Plus Platinum logo, and compared to the Cooler Master V1200, it is all but identical electrically. However, its hold-up time is much longer, thanks to larger capacitors. Ripple and noise are similar – perhaps the voltage curve on the Seasonic is slightly better.

Due to their identical genes, it is not surprising that the hybrid fan control behaves identical on both PSUs: At 40 and 200 W, the fan is off. But when it finally started up at 600 W, we were nonplussed by its noise – 42.7 dB(A) is inappropriate for a high-end PSU.

A Closer Look at the PCB

Since the Seasonic and the Cooler Master PSU are all but identical, there’s not much new to say. The primary capacitors do differ – while the Cooler Master V1200 contains one marked 390uF 420V and a few others marked 330uF 420V, all primary side capacitors in the Seasonic Platinum-1200 are marked 390uF 420V. We saw the effect of this change when we measured the hold-up times of both PSUs

  • blackmagnum
    I respect mother earth and her well-being; I will never hurt her by accepting these gluttonous monstrosities in my gaming builds. Low budget/ low power/ high efficiency FTW!
  • Alex Kelly
    Where is the EVGA Supernova P2 series? Would have been nice to see it included. :)
  • kevith
    Schön, dass Ihr auch deutsche artikeln jetzt schreibt. Das hätte ich mich nie gedacht. Aber was mit alle die amerikanischen leser? Die kann bestimmt kein deutsch?
  • damric
    Much better PSU review than usual for THW.

    However, none of these PSUs are as interesting as the SF Leadex.
  • Alex Kelly
    13853559 said:
    Much better PSU review than usual for THW.

    However, none of these PSUs are as interesting as the SF Leadex.

    Agreed! That's why I wanted to see the P2 here.
  • nikolajj

    Well, you don't seem to understand fully.
    They don't really consume more power than the connected hardware demands. On the other hand, they have an amazing efficiency rating, meaning that they use a minimum of power, and are therefore better for the planet. ;)
  • mapesdhs
    Pity the Thermaltake Toughpower XT Gold 1475W wasn't included, I've obtained
    half a dozen of them recently, excellent PSUs.


  • TheMentalist
    Cooler Master really stepped up their quality in PSU's, can't ignore that.
  • lp231
    I still like the interior of my Antec TruePower Quattro 850w. Massive heatsinks!
    About that Antec 1300w PSU, according to their site, it says that has a "20+8-pin MBU socket for the needs of tomorrow."
    Do you guys have any info on this?
  • majormajormajormajor
    "At the time of writing, the website only lists 7 Titanium-grade PSUs: Six models from a company called ‘Super Flower’ and the Corsair AX1500i"

    Wow, way to discredit yourself completely. You're reviewing power supplies and you've never heard of Super Flower?