SilverStone SX600-G SFX Power Supply Review
SilverStone is one of the few manufacturers that shows great interest in small form-factor PSUs. Aside from the compact ATX power supplies its portfolio includes, the company also has an SFX series that includes five members with capacities ranging from 300 to 600W. The two lower-output models are 80 PLUS Bronze-certified, while all the rest meet the 80 PLUS Gold requirements. Today we're taking a detailed took at the family's flagship, the SX600-G.
Since SilverStone also manufactures enclosures, it found out early that enthusiasts with small cases may need compact dimensions, but strong PSUs to support high-end components. With so many mini-ITX cases on the market, there are plenty of choices. On the other hand, there aren't a lot of SFX PSU options. That's doubly true for units with over 500W capacity exploiting a fully modular cabling design. So SilverStone practically plays alone in this arena. Fortunately, since it's quite experienced with the form factor in question, SilverStone is traditionally a trusted source for quality products. We're naturally expecting a lot out of the SX600-G, then, which we are going to put through extreme loads and hot environments. After all, inside a small chassis, temperatures can rise quickly.
Besides 80 PLUS Gold-rated efficiency and fully modular cabling, the SX600-G also enables semi-fanless operation that is deactivated (according to SilverStone's specifications) once the supply's internal temperature reaches 45 degrees Celsius. It is amazing to see such a high-capacity SFX PSU using a fanless mode, and we were interested in checking this mode's performance in the real world. Surely high efficiency plays a key role in keeping thermal dissipation at low levels. But the airflow in this unit can't be optimal, since the large components needed to generate 600W take up so much room. We'd expect the result to be a quick increase to that target 45 °C threshold once the PSU is stressed.
SilverStone's efficiency rating satisfies the 80 PLUS organization's Gold specification. That level still retains some prestige, although currently it comes third behind the 80 PLUS Platinum and Titanium certifications. To the best of our knowledge, there aren't any SFX PSUs available with higher than a Gold rating, and it definitely won't be easy to manufacture one.
The SX600-G is fully modular and supports the sleep states (C6 and C7) that Intel's Haswell-based processors introduced. In addition, it is equipped with all basic protection features, though according to SilverStone's specifications, Over-Temperature Protection (OTP) isn't available; we consider that capability to be crucial.
The maximum operating temperature at which this unit can deliver full power continuously is 40 °C, according to SilverStone. Taking into consideration the other technical specifications, we have to assume that it was hard to guarantee trouble-free operation under full load at 50 °C. However, we will follow our testing protocol that dictates full load and overload testing at 45 °C.
As for cooling, the SX600-G uses a small, double ball-bearing fan, and SilverStone exploits a semi-passive mode to make this PSU quieter at light loads. The company states that the fan starts spinning only when its internal temperature exceeds 45 °C; we will check this by testing at ambient temperatures, since the conditions in our hotbox won't allow for conditions under 45 °C. Finally, SilverStone covers this supply with a three-year warranty -- a bit brief, in our opinion, for a PSU at this price point. We would prefer a five-year guarantee.