A fully passive 850 W power supply is a notable achievement and a highly desirable product for all lovers of low-noise computer setups. The Cooler Master X Silent Edge Platinum does very well in terms of performance, too. The sole fact that it can steadily pass all tests in high ambient temperatures and deliver more than its rated power if needed, is impressive. Once we go into details, we see a very solid yet not great performance in terms of efficiency and voltage regulation. Don't get me wrong though, the results are not bad at all, you just typically build up your expectations when you're looking at a unit of this price range.

Without any discounts the power supply retails at an eye watering $549, making it two to three times more expensive than some comparably specced units with fans. When looking for power supplies without any fan, there isn't much competition. Seasonic offers the Prime Fanless, but those top out at 700 W. If you want more power than that, then the Cooler Master X Silent Edge is the only option on the market. Need more power than the tested 850 W model? Cooler Master also offers this power supply with a 1100 W rating! Still, the high price is definitely a problem when considering value, unless a silent system is extremely important for you and you're willing to pay the price.

On one hand the X Silent Edge Platinum performs well, does have quite a bit more parts in its BOM than your average high-end 850 W power supply, is completely silent and offers a 15-year warranty. On the other hand, it's very expensive, and does not perform as well as similarly priced units with fans. Subjectively, it even looks good. But do these factors make it a worthwhile deal? To some—yes, especially if the PSU could be found at a discount. Nonetheless, it is a significant unit with a significant price tag, and prospective buyers need to weigh the potential investment.