Final Analysis
The following video footage shows a brief overview and unboxing of Corsair's HX850.
This power supply boasts high performance. It's even better than the supposedly higher-end HX850i thanks to superior ripple suppression (attributable to those Type 4 cables with extra ripple filtering caps and more voltage sense wires). The price difference between both models isn't large, so anyone who doesn't prioritize low ripple might prefer the HXi's hardware monitoring and custom fan profile functionality.
Reasons to consider the vanilla HX850 are numerous, including quiet operation, fully modular cabling, excellent build quality, plenty of available connectors, a semi-passive fan mode, the ability to switch between one and multiple +12V rails, and of course the 10-year warranty.
On the other hand, there are only a few negative points: bulky ATX, EPS, and PCIe cables are an issue that most builders will complain about, and the short distance between SATA and peripheral connectors could cause compatibility problems in some enclosures.
Because of its larger footprint, which allows for a clean design and optimal airflow inside, the HX850 is a particularly quiet 850W power supply. Even when we pushed beyond its limits, the PSU's fan wasn't annoyingly loud. Surely, a depth measurement of 18cm makes the HX850 one of the largest models in its capacity class, though.
Corsair's price tag is much higher than what Seasonic charges for the impressive Focus Plus Gold 850 and EVGA for its SuperNOVA 850 G3. But neither of those two PSUs offer such quiet operation. In fact, their overall noise output exceeds 30 dB(A), so many builders consider them too loud under taxing loads.
Really, Corsair just needs to drop its price a bit to achieve a higher value score. That's what matters to most enthusiasts nowadays. At least you get what you pay for in the HX850.
Apparently you can't go wrong with a high-end Corsair PSU, especially when it's made in cooperation with Channel Well Technology. The new HX line-up continues proving to be superb in this, our third review of a model from that family. Like the HX1200 and HX1000, the HX850 also earns a recommendation, even if there are still areas we'd like to see improved. Efficiency could certainly be increased, while inrush currents with 230V input need to be lower. The 5VSB rail's OCP triggering point should be dialed down across the HX series. Hopefully Corsair implements our recommendations at some point and makes the HX850 an even more impressive piece of hardware.
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