The Corsair SF1000L is the objective winner of this comparison, securing more category wins across the evaluated specifications. Its most significant advantage over the Corsair RM850x is the inclusion of a 12VHPWR connector, which represents a 100% improvement in this specific connectivity feature. While both units offer competitive performance, the superior connector support positions the SF1000L as the more modern hardware choice for users prioritizing current interface standards.

Choose the Corsair SF1000L if you require the 12VHPWR connector for your build, as it provides a distinct advantage in modern power delivery. Conversely, opt for the Corsair RM850x if you prioritize long-term support, as it offers a warranty that is 43% better than the alternative. Your decision should ultimately depend on whether you value the latest connection standards or the extended coverage provided by the manufacturer.