Corsair Professional HX850 850W Power Supply Review

Interior Impressions

Popping the hood on this power supply reveals that it is indeed made by Channel Well Technology (CWT) much like Corsair’s TX-series. However, unlike the TX-series the HX850 is based off of a brand new platform called the DSG which is bred for high-efficiency output.


Starting with the input filter, we can see that it is well-appointed and the soldering is overall quite well done. Meanwhile, at the front of the power supply it is good to see that the fragile sleeving on the cables has been protected from scratching by a rubberized ring around the sharp edges of this PSU’s enclosure.


The primary side consists of a pair of Nippon Chemi-Con 105*C rated capacitors along with a transformer and the usual wrapped-coil design typical of Channel Well-based units. Something that really surprised us was the fact that the heatsinks within the HX850 are so small even though high spec’d rectifiers and diode packs are used. However, considering the efficiency numbers this PSU supposedly has, less heat will be generated meaning smaller heatsinks can be used.


The secondary side consists of yet more Nippon Chemi-Con capacitors along with a few solid caps here and there for some added performance. Those two small vertical PCBs you see seem to contain the +5V and +3.3V circuitry and have their own dedicated copper plates to disperse the heat they generate.


The thermal diode which is linked to the fan controller is attached to one of the primary heatsinks.


Moving on to the modular interface we are greeted with a darn-near perfect soldering job for all the traces. This really is a textbook job here and just serves to put the icing on an already impressive interior design.


The fan used on this power supply is the same as other 140mm-equipped Corsair power supplies: a 140mm Yate Loon unit with a ball bear fan which is rated to operate at a very high 2800RPM. Corsair has also seen the need to attach a clear plastic fan shroud to it in order to direct airflow to the most necessary areas.