Corsair HX 850 Watt Gold PSU review - Certification, Specs and Features

Certification

So, Corsair offers a 80+ Gold certification, tested by the 80PLUS organization (the people that certify and test efficiency). We already explained a little what that literally means. But what does such a certification entail?

Well, we have standard, bronze, silver, gold, and platinum certifications. A PSU that is certified “80 PLUS Gold” or “80 PLUS Platinum” is more efficient than a normal unit. Below you’ll find a table that shows what efficiency levels a PSU has to achieve at a given load to make the grade for a specific certification level.

The Corsair HX 850 power supplies are certified by the 80PLUS organization to deliver a 90% energy efficiency at 50% load (which equals a Gold label). We are not 100% certain if the product complies with the ErP (Energy Related Product) directive to ensure less than 1W of power is used in passive standby and off modes. We'll test that manually later on in the article.

Above, you can see a diagram of how the PSU behaves efficiency wise.

Specs and Features

HX Series Modular Power Supplies: Legendary Performance and Reliability
Corsair Professional Series HX power supplies are designed for PC builders and upgraders who need a highly efficient, quiet, and supremely-reliable power supply, with a modular cable-set that makes installation a breeze.

Quiet operation at low loads
Thanks to their highly-efficient design, Corsair Professional Series power supplies generate minimal heat, and are able to operate in a silent, fully-fanless mode at up to 20% of the PSU’s maximum load (170W for the HX850). This means that Professional Series HX PSUs will be completely silent when you’re performing less intensive tasks, such as web browsing or chatting in forums. And the thermally-controlled fan spins up gradually above 20% load, so that it still operates quietly during normal use and when gaming. Basic PC power supplies have fans that spin all the time your PC is on – whether you’re pushing your graphics card to the limit or just surfing the web – making them noisier and more intrusive.

Modular cables for easy installation
Professional Series power supplies have a comprehensive modular cable set allows you to use only the cables you need for your particular set of components. The benefits of this include a cleaner, neater installation, and that ‘professionally-built’ look, plus increased airflow through the case due to reduced cable clutter. The cables are also long enough to support full-tower cases.

80 PLUS® GOLD: High efficiency – Low heat
Efficiency is the measurement of how effectively a power supply converts the AC power from your wall outlet to the DC power used by your PC’s components. If your power supply isn’t efficient, it will generate more heat, which requires more cooling and more fan noise. And, it might even affect your power bill.

Professional Series HX Series PSUs are among the most efficient on the market. Each model has 80 PLUS Gold certification, which ensures up to 90% energy-efficiency. This helps to keep your PC cool and quiet, and it may even save you money too.

Reliable
Professional Series PSUs are built with premium components, such as 105C capacitors, and are capable of continuous power delivery at a temperature rating of 50° C, ensuring maximum performance and reliability even in the most demanding and hot-running performance PCs.
The Corsair Advantage

Corsair Professional Series PSUs are backed by a reassuring 7-year warranty and comprehensive customer support via telephone, email, forum and the Tech Support Express helpdesk.

Today’s high-performance CPUs and graphics cards all require power to be supplied over the +12V rail, which means that any PSU worth considering needs to be able to deliver the majority of its power on the +12V rail. The 850W Professional Series HX PSU features a huge 70 Amp (840 Watt) single +12V rail, which makes it ideal for high-end gaming PCs with single and multiple GPUs.