FSP Hydro G Pro 1000W ATX v3.0 Power Supply Review

The FSP Hydro G Pro 1000W has top-notch build quality and it is ATX v3.0 and PCIe 5.0 ready.

FSP Hydro G Pro 1000W ATX v3.0
(Image: © Tom's Hardware)

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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

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VoltageBeforeAfterChangePass/Fail
12V12.245V12.062V1.50%Pass
5V5.044V4.900V2.85%Pass
3.3V3.346V3.218V3.84%Pass
5VSB5.106V5.069V0.72%Pass

Advanced Transient Response at 20% – 10ms

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VoltageBeforeAfterChangePass/Fail
12V12.248V12.079V1.37%Pass
5V5.046V4.903V2.84%Pass
3.3V3.347V3.219V3.82%Pass
5VSB5.107V5.071V0.71%Pass

Advanced Transient Response at 20% – 1ms

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VoltageBeforeAfterChangePass/Fail
12V12.253V12.069V1.50%Pass
5V5.049V4.907V2.82%Pass
3.3V3.349V3.215V4.01%Pass
5VSB5.109V5.062V0.92%Pass

Advanced Transient Response at 50% – 20ms

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VoltageBeforeAfterChangePass/Fail
12V12.212V12.121V0.74%Pass
5V5.032V4.890V2.82%Pass
3.3V3.336V3.198V4.13%Pass
5VSB5.067V5.020V0.93%Pass

Advanced Transient Response at 50% – 10ms

Swipe to scroll horizontally
VoltageBeforeAfterChangePass/Fail
12V12.215V12.124V0.74%Pass
5V5.034V4.890V2.85%Pass
3.3V3.337V3.205V3.96%Pass
5VSB5.069V5.033V0.70%Pass

Advanced Transient Response at 50% – 1ms

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VoltageBeforeAfterChangePass/Fail
12V12.218V12.137V0.66%Pass
5V5.037V4.896V2.80%Pass
3.3V3.338V3.201V4.10%Pass
5VSB5.070V5.011V1.17%Pass

Transient response is good enough at 12V but mediocre at 5V and 3.3V. Nevertheless, the 12V rail is the most important. 

ATX 3.0 Transient Response Tests

The following table shows the load that we applied. 

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Duty CycleTime for Power Excursion (Te)Time Constant (Tc)Power @ TePower @ Tc
5%100μs1900μs2000W917.7W
8%1ms11.5ms1800W897.3W
12.5%10ms70ms1600W881.6W
25%100ms300ms1200W923.8W

The PSU successfully passed all ATX 3.0 transient response tests for units equipped with 12VHPWR connectors. 

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.

The spike at 5VSB looks nasty but it is below the 5.5V limit allowed by the ATX spec. 

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.

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PSU Timings Table
T1 (Power-on time) & T3 (PWR_OK delay)
LoadT1T3
20%49ms131ms
100%52ms130ms

The PWR_OK delay is within the 100-150ms region, so the PSU supports the alternative sleep mode recommended by the ATX spec.

Ripple Measurements

Ripple represents 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).

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Test12V5V3.3V5VSBPass/Fail
10% Load16.9 mV8.4 mV7.8 mV9.6 mVPass
20% Load28.0 mV13.6 mV15.8 mV43.1 mVPass
30% Load24.4 mV12.8 mV13.1 mV36.3 mVPass
40% Load14.1 mV8.3 mV8.1 mV9.3 mVPass
50% Load29.4 mV12.9 mV17.4 mV39.0 mVPass
60% Load14.9 mV9.0 mV10.6 mV11.0 mVPass
70% Load32.2 mV15.0 mV19.0 mV38.2 mVPass
80% Load15.9 mV10.8 mV14.0 mV11.7 mVPass
90% Load27.1 mV16.0 mV19.9 mV36.3 mVPass
100% Load23.0 mV11.9 mV16.2 mV14.2 mVPass
110% Load23.8 mV11.9 mV17.1 mV14.5 mVPass
Crossload 118.8 mV14.8 mV14.8 mV10.5 mVPass
Crossload 216.5 mV12.1 mV10.6 mV9.8 mVPass
Crossload 324.4 mV12.2 mV15.6 mV37.0 mVPass
Crossload 423.1 mV11.2 mV15.1 mV13.9 mVPass

Ripple suppression is good on all rails. 

Ripple At Full Load

Ripple At 110% Load

Ripple At Cross-Load 1

Ripple At Cross-Load 4

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 cause increased static noise in your headphones or/and speakers.

΅We use TekBox's EMCview to conduct our EMC pre-compliance testing.

(Image credit: Tom's Hardware)

Three spurs go over the limit with the average EMI detector, and two with the peak detector. 

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Contributing Editor

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