Fractal Design Ion SFX Gold 650W Power Supply Review

Great performance, highly modular.

(Image credit: © Fractal Design)

Why you can trust Tom's Hardware Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.

To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units. 

Primary Rails And 5VSB Load Regulation

The following charts show the main rails' voltage values recorded between a range of 40W up to the PSU's maximum specified load, along with the deviation (in percent). Tight regulation is an important consideration every time we review a power supply because it facilitates constant voltage levels despite varying loads. Tight load regulation also, among other factors, improves the system’s stability, especially under overclocked conditions and, at the same time, it applies less stress to the DC-DC converters that many system components utilize.

The load regulation is tight on all rails. 

Latest Videos FromTom's Hardware

Hold-Up Time

Put simply; hold-up time is the amount of time that the system can continue to run without shutting down or rebooting during a power interruption.

The hold-up time is much longer than the required (17ms), and the power ok signal is accurate. 

Inrush Current

Inrush current, or switch-on surge, refers to the maximum, instantaneous input current drawn by an electrical device when it is first turned on. A large enough inrush current can cause circuit breakers and fuses to trip. It can also damage switches, relays, and bridge rectifiers. As a result, the lower the inrush current of a PSU right as it is turned on, the better.

The inrush current is high, with 230V input. 

10-110% Load Tests

These tests reveal the Ion's load regulation and efficiency levels under high ambient temperatures. They also show how the fan speed profile behaves under increased operating temperatures.

Swipe to scroll horizontally
Test # 12V 5V 3.3V 5VSB DC/AC (Watts) Efficiency Fan Speed (RPM) PSU Noise (dB[A]) Temps (In/Out) PF/AC Volts
1 3.634A 1.971A 1.972A 0.977A 64.936 84.89% 876 20 40.09 C 0.927
. 11.920V 5.077V 3.351V 5.121V 76.491 . . . 44.57 C 115.12V
2 8.268A 2.959A 2.961A 1.174A 129.453 88.31% 896 20.8 40.43 C 0.952
. 11.918V 5.071V 3.346V 5.113V 146.59 . . . 45.25 C 115.12V
3 13.306A 3.454A 3.441A 1.371A 194.553 89.18% 907 21.5 41.06 C 0.966
. 11.915V 5.069V 3.343V 5.105V 218.164 . . . 46.20 C 115.12V
4 18.341A 3.949A 3.951A 1.570A 259.748 89.51% 1048 26.4 41.22 C 0.973
. 11.915V 5.068V 3.341V 5.097V 290.196 . . . 47.03 C 115.12V
5 23.048A 4.937A 4.940A 1.769A 325.093 89.05% 1551 37.1 42.81 C 0.979
. 11.913V 5.067V 3.341V 5.089V 365.052 . . . 49.14 C 115.12V
6 27.691A 5.926A 5.931A 1.969A 389.594 88.72% 1704 40.5 42.92 C 0.981
. 11.909V 5.065V 3.339V 5.080V 439.149 . . . 50.01 C 115.12V
7 32.398A 6.913A 6.923A 2.169A 454.888 88.14% 1980 43.6 43.56 C 0.982
. 11.907V 5.065V 3.338V 5.072V 516.089 . . . 51.24 C 115.12V
8 37.106A 7.902A 7.912A 2.371A 520.206 87.47% 2044 45.8 44.19 C 0.984
. 11.906V 5.064V 3.337V 5.063V 594.759 . . . 52.45 C 115.12V
9 42.213A 8.397A 8.394A 2.373A 585.108 86.94% 2049 45.9 44.27 C 0.986
. 11.906V 5.063V 3.336V 5.058V 673.021 . . . 53.19 C 115.11V
10 47.058A 8.891A 8.906A 2.975A 649.946 86.19% 2056 46.2 45.71 C 0.988
. 11.905V 5.063V 3.335V 5.043V 754.113 . . . 54.90 C 115.12V
11 52.503A 8.891A 8.904A 2.978A 714.774 85.47% 2055 46.2 46.54 C 0.99
. 11.905V 5.063V 3.336V 5.039V 836.325 . . . 56.25 C 115.11V
CL1 0.148A 12.003A 12.000A 0.000A 102.687 83.00% 1457 35.5 42.96 C 0.946
. 11.927V 5.066V 3.343V 5.125V 123.727 . . . 49.60 C 115.13V
CL2 54.021A 1.003A 1.001A 1.000A 656.529 86.85% 2058 46.2 45.51 C 0.988
. 11.903V 5.073V 3.343V 5.082V 755.914 . . . 54.84 C 115.12V

Up to the 40% load test, the fan spins at average speeds, given the load and temperature conditions, but afterward, its speed skyrockets, affecting notably the noise output. 

The APFC converter needs a slight tuning since the power factor readings are not that high even under high loads. 

20-80W Load Tests

In the following tests, we measure the Ion's efficiency at loads significantly lower than 10% of its maximum capacity (the lowest load the 80 PLUS standard measures). This is important for representing when a PC is idle with power-saving features turned on.

Swipe to scroll horizontally
Test # 12V 5V 3.3V 5VSB DC/AC (Watts) Efficiency Fan Speed (RPM) PSU Noise (dB[A]) PF/AC Volts
1 1.222A 0.493A 0.476A 0.195A 19.665 72.83% 0 less than 6.0 0.815
. 11.917V 5.082V 3.354V 5.136V 27.001 . . . 115.13V
2 2.496A 0.983A 0.985A 0.390A 40.042 81.89% 0 less than 6.0 0.896
. 11.917V 5.080V 3.352V 5.132V 48.898 . . . 115.13V
3 3.705A 1.478A 1.461A 0.585A 59.553 85.55% 0 less than 6.0 0.921
. 11.918V 5.077V 3.350V 5.127V 69.609 . . . 115.13V
4 4.979A 1.970A 1.970A 0.781A 79.942 86.77% 0 less than 6.0 0.932
. 11.919V 5.076V 3.349V 5.123V 92.131 . . . 115.13V

Under light loads there is no need for the PSU's fan to spin.

2% or 10W Load Test

Intel plans on raising the ante at efficiency levels under ultra-light loads. So from July 2020, the ATX spec will require 70% and higher efficiency with 115V input. The applied load is only 10W for PSUs with 500W and lower capacities, while for stronger units we dial 2% of their max-rated-capacity.

Swipe to scroll horizontally
Test # 12V 5V 3.3V 5VSB DC/AC (Watts) Efficiency Fan Speed (RPM) PSU Noise (dB[A]) PF/AC Volts
1 0.932A 0.205A 0.203A 0.051A 13.069 65.62% 0 less than 6.0 0.743
. 11.899V 5.070V 3.343V 5.135V 19.917 . . . 115.13V

Efficiency

The efficiency with light loads exceeds 65%, so it is quite high. Nonetheless, the ATX spec will require higher than 70% in 2020. 

Next, we plotted a chart showing the Ion’s efficiency at low loads, and loads from 10 to 110% of its maximum-rated capacity. The higher a PSU’s efficiency, the less energy goes wasted, leading to a reduced carbon footprint and lower electricity bills.

The efficiency with normal loads is low, compared to the competing offerings. With light and super-light loads, the Ion model takes its revenge, though.  

5VSB Efficiency

Swipe to scroll horizontally
Test # 5VSB DC/AC (Watts) Efficiency PF/AC Volts
1 0.100A 0.514 73.64% 0.11
. 5.135V 0.698 . 115.12V
2 0.250A 1.284 76.25% 0.223
. 5.133V 1.684 . 115.12V
3 0.550A 2.821 77.18% 0.338
. 5.128V 3.655 . 115.12V
4 1.000A 5.122 77.28% 0.407
. 5.122V 6.628 . 115.12V
5 1.500A 7.672 77.06% 0.442
. 5.114V 9.956 . 115.12V
6 3.000A 15.265 75.99% 0.487
. 5.088V 20.088 . 115.12V

The 5VSB rail has low efficiency. 

Power Consumption In Idle And Standby

Swipe to scroll horizontally
Mode 12V 5V 3.3V 5VSB Watts PF/AC Volts
Idle 11.899V 5.074V 3.347V 5.139V 5.915 0.456
. . . . . . 115.1V
Standby . . . . . 0.007
. . . . . . 115.1V

The vampire is low, something that helps the 5VSB rail's efficiency under light load. 

Fan RPM, Delta Temperature, And Output Noise

All results are obtained between an ambient temperature of 37 to 47 degrees Celsius (98.6 to 116.6 degrees Fahrenheit).

(Image credit: Tom's Hardware)

(Image credit: Tom's Hardware)

The fan profile gets aggressive, under high operating temperatures.

The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.

(Image credit: Tom's Hardware)

(Image credit: Tom's Hardware)

Even under normal operating temperatures, the fan profile gets aggressive with higher than 340W loads. 

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.