Pros, Cons, And Final Verdict
We have mixed feelings about the Twins 500W. For starters, we like the idea it's built on. However, the actual implementation could be better with some changes. If FSP provided the option to completely deactivate one module and not use both of them in parallel, then efficiency under light loads would improve significantly. In addition, there would be minimal stress applied to the module in standby, bolstering its reliability. By having both modules operate simultaneously, they endure the rigors of always-on operation, increasing the possibility that they break down at the same time, or at least close together. Given that FSP implemented a digital platform, the right modifications to hardware and software could enable FSP's Guardian app with controls to deactivate this hybrid module operation. Hopefully we see something like this in the family's next revision.
FSP's Twins 500W is an interesting PSU. It's the first server power supply designed to fit in normal ATX cases, addressing enthusiasts who need a highly reliable PSU for their home servers. The build quality is pretty good, and FSP uses top-notch components to ensure the frame and modules enjoy a long lifetime.
The major problem most folks are going to have with the Twins 500W, aside from its steep price tag, is the noise generated by those small fans in the modules. For a server system typically installed in a noisy environment, this doesn't pose a problem. But in a PC that lives in your house, that's a major con. So before you decide to invest in this PSU for a home server, take into account that it will definitely make its presence felt, especially under tough workloads. You'll want to find an isolated space for it. Conversely, if you're adverse to all of that noise, buy a high-quality desktop PSU instead and forget the redundant functionality.
Performance-wise the Twins 500W doesn't set any records, especially when it comes to load regulation and ripple suppression. But we can't forget that it belongs to a special PSU category, so comparisons to normal desktop PSUs are inherently unfair. This is a server-type unit offering increased reliability and a rich feature set attributable to its digital circuit, which facilitates monitoring via software.
We would like to see FSP use more PCIe connectors, ideally four of them, along with additional SATA connectors. You might counter that a server PSU won't be used in a gaming system, so two PCIe connectors are enough. Still, this is a server PSU addressing home users, so you never know where it'll end up. Finally, it would be nice if the next Twins generation also offered some modular cables as well. Meanwhile, we are expecting the second member of this line with increased capacity, the Twins 700W, to hit the market pretty soon.
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