Efficientcy Meets Compact Dimensions
Cooperation between EVGA and Seasonic paved the way for the SuperNOVA 550 GS, which has high efficiency levels and tight voltage regulation, and is able to offer prospective buyers peace of mind thanks to its Japanese electrolytic capacitors and five-year warranty. The fully modular cabling design is a great asset, and on top of that, this unit features a semi-passive mode that is missing from Seasonic's G-550.
Another great feature of the 550 GS is that it also has more connectors than its Seasonic competition, including four PCIe connectors that are available at the same time as two EPS connectors. This is probably overkill, since a 550W PSU would have to be fully loaded to support two high-end graphics cards and an overclocked CPU. While Seasonic was very conservative with its G-550, EVGA was more progressive with its 550 GS. We prefer EVGA’s approach though, because it offers more options to potential buyers.
The only major downside of the 550 GS compared to the G-550, which costs about the same in the United States, is greater ripple at +12V. Although this unit is made by Seasonic and utilizes a modern platform, it's clear that the company didn’t pay much attention to ripple suppression on this rail. The result doesn't please us; we expected Seasonic’s implementations to perform much better in those tests. Still, while 70mV of ripple in worst-case scenarios might be considered mediocre performance for a Seasonic PSU, it's well within ATX specs and won’t pose a threat to a system’s stability. With that said, we want to measure ripple levels below 40mV on this rail. With lower ripple at +12V, the 550 GS would achieve a much higher performance score.
Other than the increased ripple at +12V and the fan's not-so-quiet performance under stress, this PSU leaves an overall good impression. Most PCs with one graphics card are fine with 550W, so this unit would be ideal for them. If Seasonic manages to improve the platform's performance at +12V, even higher-end offerings in this wattage range will have a hard time competing with it. All in all, if you are searching for a 550W PSU that has enough connectors to support CrossFire or SLI, along with a high-end motherboard that needs both EPS and ATX12V connectors, your choices are limited; the SuperNOVA 550 GS looks like the only option.