Corsair Gold: AX850 Power Supply

Viewing page 1 of 5 pages. 1 2 3 4 5 Next
Corsair AX850 (CMPSU-850AX )
ATX Power Supply
Sample Supplier
Market Price

Corsair is arguably the most successful new power supply brand to emerge in the retail computer components landscape in the past few years. Ostensibly a memory (RAM) company for many years, Corsair's partnerships with major PSU makers — first Seasonic, then Channel-Well and Enhance — and aggressive markting/distribution efforts have established the brand firmly as a major player in power supplies. Corsair's PSU lineup is very extensive, with 21 models ranging from an entry level 400W to the newly introduced 1200W 80 Plus Gold certified AX1200.

The AX series includes two other models, the AX850 and AX750, so designated for their rated output power. Corsair sent us an sample of the AX850 for review. It's obvious to anyone who pays close attention to retail computer power supplies that the Corsair AX850 is based on Seasonic's successful high-efficiency 80 Plus Gold certified X-series, two models of which we have reviewed, the X-650 and the new fanless X-400. Looking at the Corsair web pictures of the AX750, we'd bet it is based on a Seasonic X-750, too.


The AX850 retail box is big and impressive like all the other Corsair PSUs.

Very nice packaging, including a soft pouch for the PSU and velcro-flap bag for all the output cables.

The essence of the product: Power supply and all the cables. Some are sleeved, others are in the flat data-cable style introduced with Corsair's very first power supplies. The flat profile makes those cables easier to route in some cases, important if you like the cables in your PC tidy and mostly out of sight..

FEATURE & BRIEF Our comment
Supports the latest ATX12V v2.31 and EPS 2.92 standards and is backward compatible with ATX12V 2.2 and ATX12V 2.01 systems Good.
Low-profile, flat cable design reduces air friction and helps maximize airflow through the computer's chassis
Completely modular cable system allows you to use only the cables you need. Power supply upgrade and replacement is easy, as the cables only need to be disconnected at the power supply Like Seasonic X-series.
An ultra-quiet 120mm double ball-bearing San Ace fan from industry-leader, Sanyo Denki delivers excellent airflow at an exceptionally low noise level by varying fan speed in response to temperature
Like Seasonic X-series.
Ultra Low Noise - Hybrid Silent Fan Control: Fanless mode of operation (0 rpm) up to about 20% load, a quiet, low fan speed cooling mode for typical loads up to around 50% load, and a higher performance cooling mode for more demanding loads. Like the fan-equipped Seasonic X-series.
High-quality Japanese capacitors provide uncompromised performance and reliability
Many high end PSUs flaunt this feature.
80 Plus Gold certified to deliver at least 90% efficiency at 50% load OK.
A dedicated single +12V rail offers maximum compatibility with the latest components
The madness of multiple 12V lines are behind us finally.
Safety: UL, CUL, CE, CB, FCC Class B, TÜV, CCC, C-tick Very good.
Over-voltage and over-current protection, under-voltage protection, and short circuit protection provide maximum safety to your critical system components The more the merrier.
Universal AC input from 90~264V, Active PFC for PF value of 0.99 Like most high end PSUs on the retail market.
MTBF: 100,000 hours
Very good.
Seven year warranty and lifetime access to Corsair's legendary technical support and customer service Excellent.
Size: W150 x L160 x H86 mm Slightly longer than normal.

AC Input
90~264VAC ~15A 50/60 Hz
DC Output
850W @ 50°C ambient temperature

The AX-850 is spec'd to provide 100% rated power to 50°C. This spec is more typical of server class PSUs than desktop PSUs. The whopping 70A current capacity on the 12V line is impressive, and the 3A capacity of the 5Vsb is good, but the 0.5A capacity of the -12V line(admittedly much less important) is surprisingly low.

1 2 3 4 5 Next

Power - Article Index
Help support this site, buy the Corsair Professional Series Gold AX850 850W Power Supply from one of our affiliate retailers!