Seasonic’s newest X series PSUs from the KM3 subseries carry on the glorious traditions of the earlier Gold-certified products from that brand. They are similar to their predecessors visually, come with numerous accessories, offer higher efficiency and better voltage stability, have a new operating mode for their fan and a more balanced cable system, and boast a longer warranty.
The only downside we could find in our tests was the increased level of output voltage ripple. On the other hand, this ripple is within the permissible limits, so it’s not a problem really.
Including top-wattage models, the XM subseries is not so all-around perfect. Yes, it is no worse than the earlier KM series PSUs in voltage stability or efficiency and even offers a richer selection of cables and connectors, but the KM3 subseries is better in these respects.
The key downside of the X-1050 is its rather noisy fan. Although the high-quality fan is more or less comfortable at its initial 1000 RPM, you can hardly be satisfied with it if you prefer silent computers. The Hybrid mode is not particularly useful because the PSU will only be cooled passively when idle considering its orientation at high-performance configurations with multiple graphics cards.
So, if you’re choosing between Gold-certified PSUs from Seasonic, you may want to think twice whether you really need a 1000-watt or higher PSU. Because you can instead prefer a lower-wattage model with better parameters. An 850W PSU would be quite enough for even very advanced configurations with an overclocked CPU and two graphics cards.