Seasonic Focus SGX-650 Power Supply review - Final Words & Conclusion

Final Words & Conclusion

The Seasonic Focus SGX-650 is a very good 80 Plus Gold certified power supply that stands out from the crowd mainly due to its size. It’s designed mostly for SFF systems, but you can also use it in an ATX system, with an ATX bracket. The cabling is modular and looks good enough for most users. A 10-year warranty is an outstanding plus, on par with other Focus series representatives (the ATX versions), as well as on par with for example high-end series from Corsair. 650 Watts should be sufficient most users with a single graphics card in their systems. In reality, a setup like the one used in this test (i7 8700K + GTX 1080 Ti) rarely exceeds 350 W of power draw. As far as the technical aspect is concerned, the unit is really great. Load regulation is more than ok, without noticeable droop on both +5V and +12V rails. Ripple suppression is well within tolerance levels. The 120-mm fan does its job very accurately. It’s audible only over 75% load, and below that we can say that it’s really silent. At full load, the noise is almost like that of a vacuum cleaner (it’s about 2000 rpm). The efficiency of this Seasonic PSU is really very good, reaching the declared values with ease. It’s also nice that they have used Japanese, 105°C-rated capacitors. As for the accessories, you’ll find some zip-ties, a manual, and even a PSU tester included in the package.

A word about efficiency

Same as with other power supplies, 50% of the maximum load is where the device is the most efficient. At this sweet spot, the Seasonic FOCUS SGX-650 achieved a bit above 92 % (at 230 Volts). In the case of this particular unit, half of the maximum wattage is 325 W. The average gaming PC with a single graphics card (at least the ones that are usually spotted in Steam hardware polls) usually won’t exceed this value. Don’t overestimate the savings (electric bill) that you can make by going from 80 Plus Bronze to even Titanium. You can assume that the build quality of a more expensive PSUs can be higher, but the differences in efficiency are not that significant. Below, you can find the cost (in EUR) of daily use of a PC (230 Volts, 20 euro cents per kWh of power) with a power draw of 325 W (a higher-end setup with potential overclocking).

Let's assume that you play games 3 hours a day, 5 days a week, for a full year. Your PC would consume 325 Watts (= a fairly high-end setup). If we assume a cost of 20 cents per every KWh of power, you can see that the savings would be close to 8 euros at best for the entire year. This means that you would have to use the PSU for several years to make up for the difference in purchase price. Obviously, if your PC is on 24/7 it can be worth it to invest in a PSU with a higher-tier certificate, but you need to do the math yourself.  So, summing it up, an 80 Plus Gold PSU like the reviewed Seasonic Focus SGX-650 is a good compromise. In this price bracket, you should look at the features (like cables) and overall quality. In Europe, the Seasonic costs about 130 EUR.

Stability

There isn’t really much to say about stability. The voltages are stable even under higher loads. The 650 W version (there is also a 450 variant) should be enough even for dual-GPU setups with cards like a Nvidia Geforce GTX/RTX 1070/2070.

Aesthetics

The Seasonic PSU looks nice with all-black cabling, even though the cables are not sleeved. One thing that draws attention is the size: it’s a 125 mm unit with a 120 mm fan! The modular design lets you plug in only the leads that you really need, and this will certainly improve the looks of your build.

Final words

The Focus SGX-650 retails for 130 EUR and it’s not pricey. It offers attractive looks (though nowadays it’s most likely to be hidden in a shroud), very decent acoustics, and an excellent build quality. For all its compactness (due to the SFX-L form factor), the Seasonic FOCUS SGX-650 power supply showed impressive results. Firstly, it remains quiet even at loads up to 75%. Secondly, it offers over 90% efficiency. The fan does its job very well, especially if you consider that the package is very compact. The 80 Plus Gold certificate is the best price compromise for typical use (not 24/7), so in fact you don’t really need to look for an offer with a higher certificate (realistically speaking). The fully modular design makes life easier (still - you always plug the 24-pin and 4/8-pin ATX connector anyway). You can use only the cables that you really need. The cables are not sleeved, which might be a good thing for some users, and not really an advantage for others, so this is rather subjective. Included in the package, you receive a PSU tester, ATX brackets (but in fact you can use this PSU only in smaller ATX cases due to the length of the cables), zip ties, and a manual – there’s nothing missing from the “must have” list. The 10-year warranty is very good, and it’s nothing to complain about either.

Overall, we can sincerely recommend this one.

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