Rosewill Capstone-G1200 PSU Review

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Ripple Measurements

To learn how we measure ripple, please click here.

The following table includes the ripple levels we measured on the Capstone-G1200's rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).

Swipe to scroll horizontally
10% Load22.3mV7.7mV8.8mV5.3mVPass
20% Load26.5mV8.3mV8.9mV5.9mVPass
30% Load31.0mV8.8mV10.5mV6.3mVPass
40% Load36.6mV9.4mV11.2mV6.7mVPass
50% Load42.7mV11.2mV12.7mV7.8mVPass
60% Load44.9mV12.8mV13.1mV8.1mVPass
70% Load54.0mV15.0mV15.2mV8.9mVPass
80% Load62.2mV17.4mV17.6mV9.8mVPass
90% Load71.2mV19.8mV18.3mV9.7mVPass
100% Load82.4mV21.5mV23.6mV11.3mVPass
110% Load92.5mV23.2mV25.9mV12.3mVPass
Cross-Load 137.4mV20.1mV22.2mV20.3mVPass
Cross-Load 277.5mV14.8mV15.1mV7.3mVPass

Ripple suppression on the +12V rail is flat-out bad. We don't want to see anything above 50mV on this rail, especially in PSUs that cost more than $100. Usually, good PSUs register up to 40mV of ripple at +12V and the extraordinary ones stay below 20mV.

At least ripple suppression on the other rails is good enough. Still, what matters most is the +12V rail's performance, since it's used by most system components nowadays.

Ripple Oscilloscope Screenshots

The following oscilloscope screenshots illustrate the AC ripple and noise registered on the main rails (+12V, 5V, 3.3V and 5VSB). The bigger the fluctuations on the screen, the bigger the ripple/noise. We set 0.01V/Div (each vertical division/box equals 0.01V) as the standard for all measurements.

Ripple At Full Load

Ripple At 110-Percent Load

Ripple At Cross-Load 1

Ripple At Cross-Load 2

Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

  • Giannis Karagiannis
    Quite low price for a 1200W unit but considering everything else I dont think its a good buy. Try better next time Rosewill...
  • Dark Lord of Tech
    Rosewill does have some Capstones that are great quality , The Super Flower models.
  • Dark Lord of Tech
    Also Enhance released a lot of nice V and VS series models for Cooler Master.
  • Aris_Mp
    Those older Capstones are EOL because they were older platforms which most likely aren't produced any more and on top of that Super Flower lately cannot meet demand, as the rumors say.
  • Dark Lord of Tech
    Super Flower is still pushing out a lot of units , I own 5 of he EVGA Super Flowers.

    The olser Capstones are solid , they are EOL , but were very good.
  • damric
    RIP Golden Green. You will be missed.
  • DSzymborski
    Really disappointing to see Rosewill slide back - those older Capstones made by Super Flower were really quite nice and you could frequently get excellent deals on them and I made a couple of builds for people with the semi-modular gold 750s. Too bad.
  • MasterMace
    It's too bad, the previous Capstones were so nice. This makes me wonder if they should have slapped a lower rating on this unit, instead of overshooting for a Gold 1200
  • firefoxx04
    I wish manufacturers didn't bother making crap power supplies for enthusiasts markets. The fact that they even sell is a huge problem.
  • Slobodan-888
    LOL, ripple is fine. It is within ATX specifications which states that is is allowed up to 120 mVpp RMS on 12 V rail.