Corsair AX1000 PSU Review: Titanium-Class Efficiency, at a Premium Price

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Transient Response Tests, Ripple Measurements and EMC Pre-Compliance Testing

Advanced Transient Response Tests

For details on our transient response testing, please click here.

In the real world, power supplies are always working with loads that change. It's of immense importance, then, for the PSU to keep its rails within the ATX specification's defined ranges. The smaller the deviations, the more stable your PC will be with less stress applied to its components. 

We should note that the ATX spec requires capacitive loading during the transient rests, but in our methodology we chose to apply the worst case scenario with no extra capacitance on the rails. 

Advanced Transient Response at 20 Percent – 200ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.166V12.075V0.75%Pass
5V5.050V5.001V0.97%Pass
3.3V3.356V3.285V2.12%Pass
5VSB5.036V5.001V0.69%Pass

Advanced Transient Response at 20 Percent – 20ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.166V12.041V1.03%Pass
5V5.051V4.993V1.15%Pass
3.3V3.356V3.269V2.59%Pass
5VSB5.037V4.999V0.75%Pass

Advanced Transient Response at 20 Percent – 1ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.165V12.071V0.77%Pass
5V5.052V4.993V1.17%Pass
3.3V3.357V3.262V2.83%Pass
5VSB5.038V4.987V1.01%Pass

Advanced Transient Response at 50 Percent – 200ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.158V12.128V0.25%Pass
5V5.044V4.997V0.93%Pass
3.3V3.353V3.279V2.21%Pass
5VSB5.023V4.975V0.96%Pass

Advanced Transient Response at 50 Percent – 20ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.158V12.107V0.42%Pass
5V5.044V4.989V1.09%Pass
3.3V3.353V3.264V2.65%Pass
5VSB5.024V4.977V0.94%Pass

Advanced Transient Response at 50 Percent – 1ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.157V12.113V0.36%Pass
5V5.045V4.989V1.11%Pass
3.3V3.354V3.262V2.74%Pass
5VSB5.025V4.962V1.25%Pass

The results from each rail are very good. Particularly on the all-important +12V rail, registered deviations are low.

Turn-On Transient Tests

In the next set of tests, we measure the PSU's response in simpler transient load scenarios—during its power-on phase. Ideally, we don't want to see any voltage overshoots or spikes since those put a lot of stress on the DC-DC converters of installed components.

There aren't any notable spikes or voltage overshoots to report, so everything checks out.

Ripple Measurements

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Test12V5V3.3V5VSBPass/Fail
10% Load12.5mV9.7mV12.9mV10.7mVPass
20% Load13.0mV5.2mV10.8mV12.7mVPass
30% Load6.7mV5.0mV10.1mV9.1mVPass
40% Load7.7mV6.4mV9.1mV7.3mVPass
50% Load8.4mV5.0mV8.7mV7.2mVPass
60% Load8.8mV5.2mV9.0mV7.4mVPass
70% Load9.7mV5.3mV9.1mV8.2mVPass
80% Load10.4mV5.5mV9.8mV8.5mVPass
90% Load10.9mV5.6mV10.1mV8.4mVPass
100% Load15.2mV6.5mV10.7mV9.6mVPass
110% Load15.7mV6.6mV11.0mV9.9mVPass
Cross-Load 115.2mV5.2mV11.6mV7.0mVPass
Cross-Load 215.1mV6.2mV9.5mV9.0mVPass

Ripple At Full Load

Ripple At 110-Percent Load

Ripple At Cross-Load 1

Ripple At Cross-Load 2

EMI Results – Average & Peak Detector

The EMI emissions we observe remain much lower than their allowable limits. Obviously, the AX1000's EMI filter does its job well.

MORE: Best Power Supplies

MORE: How We Test Power Supplies

MORE: All Power Supply Content

Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.

  • Dark Lord of Tech
    Great review , thanks , much appreciated.
    Reply
  • Aris_Mp
    Thank you! There were some changes also in the format.. Made it easier to follow :)
    Reply
  • marcelo_vidal
    evga 430 die in one year =) if you do the math you will spend 370 on cheap evgas or you can pay 27 dollars for year to get a monster
    Reply
  • wdnemesis
    I would like to see Cable Mod team up with Corsair and seasonic. I prefer cable Mod cables. The Corsair ones look fine but most people that purchase this type probably use modded cables as well. This PSU would be amazing with that option.
    Reply
  • drtweak
    I just got a AXi1200i on Newegg. Damn good price. Was on sale for 149.99 + a 20 dollar mail in rebate. I love using it with the Corsair link software and watching this baby be 91-93% Efficient all the time. I had a CM600 before which was fine, but between planed upgrades soon, and also combining my plex server with my gaming PC, 600 wasn't enough power, amps, or connectors to power a FX8320 OC'ed, GTX 960, and 13 hard drives lol
    Reply
  • PapaCrazy
    21722950 said:
    I just got a AXi1200i on Newegg. Damn good price. Was on sale for 149.99 + a 20 dollar mail in rebate. I love using it with the Corsair link software and watching this baby be 91-93% Efficient all the time. I had a CM600 before which was fine, but between planed upgrades soon, and also combining my plex server with my gaming PC, 600 wasn't enough power, amps, or connectors to power a FX8320 OC'ed, GTX 960, and 13 hard drives lol

    Hard drive power requirements can sneak up on you. I once plugged too many HDDs into a SATA line and started having drives randomly disconnect. I think I might have corrupted them that way.

    Reply
  • jimmysmitty
    21722950 said:
    I just got a AXi1200i on Newegg. Damn good price. Was on sale for 149.99 + a 20 dollar mail in rebate. I love using it with the Corsair link software and watching this baby be 91-93% Efficient all the time. I had a CM600 before which was fine, but between planed upgrades soon, and also combining my plex server with my gaming PC, 600 wasn't enough power, amps, or connectors to power a FX8320 OC'ed, GTX 960, and 13 hard drives lol

    I got a AX860i for less than retail as I worked at a repair shop so discount about 5 years ago and its still going. its a great little unit. I still think the AXi series is one of the best PSUs out there and worth the money.
    Reply
  • Dark Lord of Tech
    I have the RM1000i White Special Edition which was limited to 100 total units. Great PSU.
    Reply
  • BoredErica
    From 0-300w it seems cooler than passive 600w Seasonic PSU. Did you remeasure the PSUs since a year ago?
    Reply