SilverStone SX600-G SFX Power Supply Review

Efficiency, Temperatures And Noise

Efficiency

Using the previous page's results, we plotted a chart showing efficiency of the SX600-G at low loads and at loads equal to 10 percent to 105 percent of the PSU's maximum.

As expected, the unit registers 2-2.5 percent higher efficiency with 230V than 115V. Simply put, this has to do with the fewer amperes required for the same amount of load, leading to lower energy losses. The SX600-G performs well in our efficiency calculations, even against larger 80 PLUS Gold-certified units. Its performance is especially great at low loads, rendering this PSU the ideal choice for a system with low-energy consumption at idle.

Efficiency At Low Loads

In the next tests, we measured the efficiency of the SX600-G at loads significantly lower than 10 percent of the device's maximum (the lowest load the 80 PLUS standard measures). The loads we dialed were 20, 40, 60 and 80 W. This is important for representing when a PC is idle with power-saving features turned on.

Efficiency at Low Loads
SilverStone SX600-G
Test#
12V
5V
3.3V
5VSB
DC/AC Watts
Efficiency
Fan Speed (RPM)
Fan Noise (dB[A])
PF/AC Volts
1
1.202A
0.490A
0.475A
0.195A
19.61
67.23%
1235
27.2
0.816
12.121V
5.023V
3.358V
5.048V
29.17
115.1V
2
2.434A
0.988A
0.982A
0.395A
39.73
75.16%
1400
30.1
0.920
12.115V
5.020V
3.355V
5.039V
52.86
115.1V
3
3.668A
1.485A
1.490A
5.030A
59.86
82.51%
1525
33.8
0.954
12.112V
5.018V
3.350V
5.030V
72.55
115.1V
4
4.886A
1.993A
1.970A
0.796A
79.75
85.14%
1570
34.4
0.966
12.109V
5.013V
3.347V
5.022V
93.67
115.1V

At only 20 W, efficiency drops below 70 percent. But in the other three tests it goes significantly higher, and during the last two low-load tests the 80 percent mark is easily broken. Due to the high operating temperature (above 34 °C), the semi-passive mode wasn't active. But the fan's noise wasn't annoying, either. Still, according to SilverStone, this PSU should be in passive mode until the internal temperature hits 45 °C, and we are pretty sure that at least during the 20 W load test, this threshold was not broken.

5VSB Efficiency

The ATX specification states that 5VSB standby supply efficiency should be as high as possible, recommending 50 percent or higher efficiency with 100mA of load, 60 percent or higher with 250mA of load and 70 percent or higher with 1A or more of load.

We took four measurements: one each at 100, 250 and 1000mA, and one with the full load the 5VSB rail can handle. 

5VSB Efficiency
SilverStone SX600-G
Test#
5VSB
DC/AC Watts
Efficiency
PF/AC Volts
1
0.102A
0.52
53.61%
0.084
5.054V
0.97
115.5V
2
0.252A
1.27
64.14%
0.162
5.051V
1.98
115.5V
3
10..2A
5.04
74.89%
0.327
5.034V
6.73
115.3V
4
2.502A
12.50
74.49%
0.442
4.998V
16.78
115.4V

At 5VSB, the efficiency readings are average. We expected higher efficiency on this rail, especially from a Gold-rated unit.

Power Consumption in Idle And Standby

In the table below, you'll find the power consumption and voltage values of all rails except -12V when the PSU is idle (powered on but without any load on its rails), and the power consumption when it's in standby mode (without any load at 5VSB).








Mode
12V
5V
3.3V
5VSB
Watts
PF/AC Volts
Idle
12.126V
5.025V
3.364V
5.056V
5.32
0.343
115.4V
Standby




0.34
0.030
115.6V

Power consumption at standby and with 115 V is significantly higher than 230 V input. However, it's still below 0.5 W, so this unit meets the ErP Lot 6 2013 requirements.

Fan RPM, Delta Temperature And Output Noise

The cooling fan's speed (RPMs), and delta between input and output temperature are illustrated in the following chart. The results were obtained at 34-45 °C ambient.   

At high operating temperatures, the fan speed comes close to 3600 RPM.

This next chart shows the cooling fan's speed (RPMs) and output noise. We measured acoustics from one meter away, inside a small, custom-made anechoic chamber with internals completely covered in soundproofing material (be quiet! Noise Absorber kit). Background noise inside the anechoic chamber was below 20 dB(A) during testing, and the results were obtained with the PSU operating at 34 to 45 °C ambient temperature. 

The noise can exceed 52 dB(A) if you stress the PSU like we did. It's definitely loud.

The following graph illustrates the fan's output noise over the entire operating range of the PSU. The same conditions of the above graph apply to our measurements, though the ambient temperature was between 28 and 30 °C.

The above graph was made using data gathered while the PSU was operating at normal ambient temperatures, and it shows that passive mode lasts only for a short period. We are not surprised by this. In such a small PSU with restricted airflow, it would be dangerous to allow fanless operation under any significant load.

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14 comments
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  • Dark Lord of Tech
    Price is a little high.
  • Onus
    The price is a little high.
    I'm not sure I agree with such high ratings of some of the Corsair units, with as many failures as they apparently experience within the first year. It also doesn't bode well for the poor capacitors in this Silverstone either. So far though, at this level, there is no other choice.
  • damric
    The review was perfect this time, Aris. My only nitpick is the graphs are hard to read.

    Well done.

    As far as the PSU itself, I was turned off by the 40C max operating temp fan kicks up at 45... bah... If they would have used better caps then temp could easily been rated for 50C.
  • David Dewis
    I wanna use this to run a GTX 980 in the Silverstone RVZ02 with a i5-4670 (non K) That is all.
  • g-unit1111
    Nice to see that manufacturers are starting to take small form factor builds seriously. I especially like the direction that Silverstone is going in. First the RVZ02B now high quality SFF power supplies. Wave of the future?
  • DarkSable
    This is a wonderful power supply, if you aren't pushing it altogether too hard.

    @David Dewis, go look at the Sandia Cooler. When you're done lusting after that, look at the Id-cooling Is-vc45 Vapor Chamber CPU Cooler... which you can buy right now and use to overclock an i5 in the new Raven just fine. I've got my media PC in an RVZ01 with a Pentium anniversary edition overclocked to heck, and it does just fine. (I can't wait for the RVZ02 to put my gaming rig in and run watercooling out the back.)
  • DarkSable
    That being said. Tom's. What are you doing.

    Silverstone just released the SX500-LG, which is a very slightly longer (130mm) SFX-profile power supply that fits a 120mm fan on top, instead of a dinky, noisy 80mm fan. That's the power supply that I want to see a review of!
  • g-unit1111
    933870 said:
    (I can't wait for the RVZ02 to put my gaming rig in and run watercooling out the back.)


    I very badly want a RVZ02, it will make a nice home for my old i5-3570K. :lol:
  • Grognak
    52dB and more than 25 idle... "Tiny box that makes a lot of noise" isn't my definition of SFF.
  • Aris_Mp
    I will ask for the SX-500LG, however I have many samples to process till its turn comes to hit the test bench. Unfortunately a full PSU review needs lots of time and I won't do rushed reviews.
  • Geoff C
    I converted my i7 920 (ATX Mobo) and 7970 to an SFF case 12"x17"x4" last year and have been powering it off of Silverstone's previous SFX450 - I know I'm pushing the power supply long and hard (and when gaming and taxing the CPU and GPU the PSU fan also really spins up).

    Any way to compare/contrast the SFX450 vs the 600? I know its an extra $130 but I'm tempted to upgrade the PSU in the next 6 months just because I know I'm taxing it by running it so hard...
  • warmon6
    @Grognak,

    Good thing SFF means "small form factor" and not "Low Noise Form Factor" :lol:
  • Aris_Mp
    @Geoff C

    You can read the review of the SFX450 below. It was made with the same equipment so the results are comparable.

    http://www.techpowerup.com/reviews/Silverstone/ST45SF-G/
  • arossetti
    I have this PSU in an NCase M1 V2. I've never experienced and issue with it and to me it's dead silent. It's a little on the pricey side but for my case it was really the only option for building as high performance ITX build with the NCase.