A New Corsair RM850x For 2025

A Long Running PSU Line Improves

We’ve done many a review of Corsair’s RMX850x PSUs, as they offer a renewed model every year to tempt you.  This year you can enjoy a physical dial on the back to give you direct control of the fan speed, sadly it doesn’t go up to 11.  As you should expect, it is an ATX 3.1 PSU however the new and improved 12VHPWR cable might surprise you.  It is properly called a 12V-2×6 connector and it sports shorter sensing pins and longer conductor terminals which should make the connector far more trustworthy.  The cable is rated for up to 675W of power delivery.

The RMX850x has multiple rails, both the +3.3V and +5V rails can provide up to 20A, while the main +12V rail will feed that GPU up to 70.8A.  If you leave the fan speed knob alone, the 140 mm FDB fan won’t kick in until the RMX850x has 450W load and even at full load the noise won’t exceed 31 dBA.  If you happen to need a PSU of reasonable wattage, this one comes highly recommended from Guru of 3D.  If you need over a kilowatt of power just scroll down to see several reviews to check out.