vacancies advertise contact news tip The Vault
facebook rss twitter

Corsair HX850 power supply: filling the void

by Tarinder Sandhu on 27 May 2009, 16:25

Tags: HX850, Corsair

Quick Link:

Add to My Vault: x

What makes the Corsair HX850 tick

Busting out the specs first.

Corsair HX850
Rated output power 850W @ up to 50°C
Power specification ATX12V 2.3/EPS12 v2.91
Power switch Yes
Efficiency 85% @ 20% load
88% @ 50% load
85% @ 100% load
80 PLUS certification Silver*
Input voltage (AC) Auto-ranging 90-264v, 47-63Hz
Fan(s) 1 x 140mm
Operating temperature range 0-50°C
Cable runs (pre-attached)

24-pin EATX (split)

EPS (8-pin) 

1 x 6+2 PEG 
1 x 6+2 PEG

Cable runs (modular, flat) EPS (8-pin)

1 x 6-pin PEG
1 x 6-pin PEG
1 x 8-pin PEG
1 x 8-pin PEG

2 x 4-pin Molex,
2 x 4-pin Molex 
4 x 4-pin Molex, 1x floppy 
4 x 4-pin Molex, 1x floppy 

2 x SATA 
2 x SATA
4 x SATA 
4 x SATA

Max. currents

+3.3V: 25A
+5V: 25A
+12V: 70A (single-rail design)
-12V: 0.8A
+5vSB: 3A

Max combined 3.3V & 5V output N/A
Dimension (W x H x L) 150 x 86 x 180mm
Warranty 7-year, limited
Price £140

* Corsair claims to have attained the 80 PLUS Silver classification but the results don't yet appear to have been uploaded to the database.


Inevitably, the Corsair HX850 shares many of the performance-orientated characteristics as its bigger and more expensive brother, the HX1000W. Both PSUs are based on Channel Well Technology's designs but are heavily modified for better-than-default performance, according to Corsair. Both share a 140mm temperature-controlled, double-ball-bearing fan; are equipped with 105°C-rated capacities; use DC-to-DC conversion for the 3.3V and 5V lines, and are certified for three-way SLI.

Further, the modular cable-runs are flat, good for airflow and aesthetics. We like the fact that the PSUs are rated to a specified wattage with an ambient temperature of up to 50°C, intimating that they can be pushed farther in regular conditions.

There are a few differences between the two, however, reinforcing the fact that they're not the same PSU rebadged as a lower-capacity model. The 750W/850W models use a single 12V source that's shared for the wattage-hungry components, including graphics cards and CPU(s). One benefit of such an approach lies with the ability to provide power to components whose peak usage may well trip many-railed power supplies.

The mid-range models are also 20mm shorter than the HX1000 although the other dimensions remain the same. The warranty, too, is different, as Corsair ramps it up to seven-year cover instead of five. Lastly, the new HX-series PSUs are ATX12V 2.3 compliant, as opposed to ATX12V 2.2, and the main differences pertain to increased efficiency and a slight change to the CPU's 12V requirements for the V2.3 spec.

Phew, lots of writing and no pictures. Rectify this egregious wrong by clicking on the next page.