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Advanced Transient Response Tests
For details about 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 also choose to apply a worst case scenario with no additional capacitance on the rails.
Advanced Transient Response at 20% – 20ms
Advanced Transient Response at 20% – 10ms
Advanced Transient Response at 20% – 1ms
Advanced Transient Response at 50% – 20ms
Advanced Transient Response at 50% – 10ms
Advanced Transient Response at 50% – 1ms
Results 25-29: Transient Response
The transient response is good at 12V, but nothing can beat Super Flower's Leadex platform (used by the EVGA 1600 T2) in this area. Voltage deviations are low in the other rails, too.
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.
Turn-On Transient Response Scope Shots
Fantastic performance here, with no notable spikes or voltage overshoots.
Power Supply Timing Tests
There are several signals generated by the power supply, which need to be within specified, by the ATX spec, ranges. If they are not, there can be compatibility issues with other system parts, especially mainboards. From year 2020, the PSU's Power-on time (T1) has to be lower than 150ms and the PWR_OK delay (T3) from 100 to 150ms, to be compatible with the Alternative Sleep Mode.
|T1 (Power-on time) & T3 (PWR_OK delay)|
The PWR_OK delay is lower than 150ms during the first test and slightly higher in the second, so we can safely assume that this PSU will support the alternative sleep mode once it becomes available to mainboards.
Ripple represent the AC fluctuations (periodic) and noise (random) found in the PSU's DC rails. This phenomenon significantly decreases the capacitors' lifespan because it causes them to run hotter. A 10-degree Celsius increase can cut into a cap's useful life by 50%. Ripple also plays an important role in overall system stability, especially when overclocking is involved.
The ripple limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V, and 5VSB).
|10% Load||11.6 mV||6.0 mV||3.9 mV||4.7 mV||Pass|
|20% Load||13.2 mV||6.0 mV||4.6 mV||4.7 mV||Pass|
|30% Load||14.3 mV||6.1 mV||4.6 mV||4.8 mV||Pass|
|40% Load||16.6 mV||6.1 mV||4.5 mV||5.3 mV||Pass|
|50% Load||17.9 mV||6.3 mV||5.0 mV||5.5 mV||Pass|
|60% Load||19.6 mV||7.3 mV||5.2 mV||5.9 mV||Pass|
|70% Load||21.6 mV||7.3 mV||5.4 mV||6.5 mV||Pass|
|80% Load||25.7 mV||9.1 mV||9.7 mV||7.0 mV||Pass|
|90% Load||25.5 mV||8.6 mV||10.4 mV||7.7 mV||Pass|
|100% Load||31.7 mV||9.1 mV||10.6 mV||8.4 mV||Pass|
|Crossload 1||14.3 mV||7.3 mV||11.4 mV||6.7 mV||Pass|
|Crossload 2||29.3 mV||8.0 mV||5.6 mV||7.5 mV||Pass|
Results 30-33: Ripple Suppression
Ripple suppression is good, especially on the minor rails. But nothing can even touch the AX1600i at 12V.
Ripple At Full Load
Ripple Full Load Scope Shots
Ripple At Cross-Load 1
Ripple CL1 Load Scope Shots
Ripple At Cross-Load 2
Ripple CL2 Load Scope Shots
EMC Pre-Compliance Testing – Average & Quasi-Peak EMI Detector Results
Electromagnetic Compatibility (EMC) is the ability of a device to operate properly in its environment without disrupting the proper operation of other nearby devices.
Electromagnetic Interference (EMI) stands for the electromagnetic energy a device emits, and it can cause problems in other nearby devices if too high. For example, it can be the cause of increased static noise in your headphones or/and speakers.
Things don't look so good here since we measured lots of high EMI spikes at 1 MHz and 600 kHz.
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Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.
Been trying to find a Corsair AX and EVGA T2 and nobody has them on stock!Reply
Try the EVGA G+ instead, or you could buy the Dark Power Pro 12 on Amazon right now with the 1200W in stock and the 1500W coming and able to be ordered.tamalero said:Been trying to find a Corsair AX and EVGA T2 and nobody has them on stock!
I've never seen a power supply with an "overclock" jumper/setting. You mention that this has it, and that it combines the 'virtual' single 12v rails into a single big one, but not what that means.Reply