Final Analysis
The white version of Corsair's RM850x offers the same high performance as its black counterpart, and is super quiet as well. We love the unique look of its paint job and individually sleeved cables. If you own a matching chassis or simply want a PSU that stands out from the crowd, the white RM850x and RM750x are both excellent options.
Compared to the black/charcoal RMx units at similar capacity points, the white ones cost $30 more due to those harder-to-manufacture cables. Given that a high-quality sleeving kit can cost anywhere from $80 to $100, though, a $30 premium isn't bad. Good looks don't come cheap, after all.
Corsair's RMx line is already popular among enthusiasts since all of its members offer high performance, good value ratings, and low noise output. These days, more and more users care about quiet operation, and PSUs play a big role in achieving this. A few years ago, aggressive fan profiles were preferred since efficiency levels were low. Inevitably, the PSU's fan had to cope with increased thermal loads. But now that the highest-end platforms offer sky-high efficiency, semi-passive modes are much more common and fans don't need intrusive rotational speeds to keep up with energy losses. Even the heat sinks in many PSUs are much smaller now. Corsair's RMx family doesn't employ a real heat sink for the +12V FETs.
Despite the rifle bearing fan, which can't match the lifetime of a true FDB-based fan, Corsair backs its RMx PSUs with an impressive 10-year warranty. This clearly shows confidence in the platform's reliability. Ten years sounds like a long time for rifle bearings. However, thanks to the semi-passive mode, we aren't expecting issues under normal conditions. Granted, that might not be the case if you use the RM850x in a mining rig.
The white RM850x stands alone, for the most part, until companies like EVGA and Seasonic decide to launch their own white models with similar capacity and comparably low noise output.
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