The Downsizing Effect Hits the PSU Market
As with the automotive market, downsizing is popular in PSUs, too. SilverStone has a long history of selling small and beefy power supplies, the most recent example being its Strider Gold S 1500 W. In this case, the SX600-G is among the strongest SFX units available, equipped with noteworthy features like 80 PLUS Gold efficiency and a fully modular cabling design. Besides that, it exploits semi-passive operation, which we discovered doesn't last long. Frankly, we aren't big fans of the semi-passive mode; we prefer active cooling throughout all load ranges. Just keep the fan spinning slowly during light loads. This ensures higher reliability since it applies less stress to sensitive components like the electrolytic capacitors.
If we set aside the ripple problem that we spotted at temperatures exceeding 40 °C (the limit for continuous full-load operation), this PSU's overall performance is quite satisfactory. The truth is that you don't have many options in this category, and if you want a branded SFX power supply capable of dishing out 600W, then SilverStone's offering is a one-way road. We believe that with increased airflow on the secondary side, where the most sensitive components are located, and with a better choice of capacitors, performance and reliability could be hugely improved. The weird mix of Japanese and Taiwanese caps used by Enhance, this model's OEM, troubled us. If we were SilverStone, we would demand the exclusive use of Japanese caps, which tend to perform at a higher level for much longer. In a PSU that costs $140, it is simply unacceptable to find Sus'con capacitors, which in our experience are on the same level as cheap Chinese caps.
SilverStone plays alone in the SFX field, at least when it comes to high-capacity models. The company has a rich portfolio with the SX600-G as its flagship. If you need to drive a capable mini-ITX system, and your chassis has enough airflow to avoid operating temperatures above 40 °C, then this PSU is ideal. It'd be futile to expect minimal noise output from a small PSU like this one. However, according to our sound measurements, if you can keep temperatures low, the fan speed won't be annoying. The situation can easily change at higher temperatures, where the fan's noise gets a lot louder. Two other changes could enhance this unit's usability: the addition of an on/off switch and another pair of PCIe connectors. A PSU with 600W maximum output will easily handle two mid-level graphics cards with a pair of auxiliary connectors.
The SilverStone SX600-G is among the strongest SFX PSUs available on the market today. It's an efficient unit that offers good ripple suppression at below 40 °C operating temperatures. It's able to offer good enough load regulation at +12V for an AFX PSU and was able to successfully pass all advanced transient load tests.
However, the PSU wasn't able to deliver full power flawlessly at 45 °C ambient and showed excess ripple during the full load and overload tests with over 40 °C ambient. And the semi-passive operation doesn't last long, even at normal ambient. We would also like to see the unit with four PCIe connectors instead of only two and with an accessible on/off switch as well.