Seasonic promises that the M12II EVO 620W can deliver 48A on its single 12V rail and it performs quite well up to and including loads of 300W, with stable voltages and low ripple values. At higher loads, performance is still quite good, though voltages do drop off a little, with the 12V rail reaching a low of 11.76V under a mighty 600W load. Efficiency also tails off beyond 300W and, after the abysmal Codegen PSU, the M12II EVO is the least efficient model in the test – to be clear, however, it performs a solid 12 percent better than the Codegen, so the two are still world's apart. Under low loads, the difference with most of the Gold certified models is negligible.

The Seasonic M12II-620Bronze is a new midrange power supply from Seasonic that has most all of the characteristics we have come to expect from Seasonic. The unit features a large single overhead fan that is quiet, has good efficiency values, a semi-modular design, and enough power and connectors to run the majority of systems that users will be building. In addition to these design aspects the M12II-620Bronze also has very good DC Output Quality and is very well built.

Power supplies are the unsung heroes of dependable enthusiast PCs. Processors, GPUs, and SSDs get all of the glory. They’re the components speeding up your operating system boot time. They improve frame rates, making your games more realistic. And they...