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Corsair HX850 review

Our Rating :
Price when reviewed : £130
inc VAT

Excellent efficiency, very quiet and extremely flexible - an excellent PSU

If you’re looking for a high-quality PSU with plenty of power and lots of flexibility, then the Corsair HX850 could just be the model that you’re looking for.

This 850W power supply has an 80 Plus Gold certification, which means that it’s at least 88 per cent efficient at all loads. In our tests it beat the certification throughout, managing 88.56 per cent at 100 per cent load, 90.72 per cent at 50 per cent load and 88.6 per cent at 20 per cent load. That means that it’s going to be comparatively cheap to run.

Corsair HX850 efficiency

The 80 Plus Gold certification means that this is a very efficient PSU

We’re pleased to say that it’s a very quiet power supply, too. We found that up to loads of 500W, the HX850 didn’t even need to turn its fan on, making it silent. Even at higher loads, though, it wasn’t loud and this is a quiet and efficient PSU.

Flexibility is also very good thanks to the modular design, with only the motherboard, CPU and two PCI Express 6+2-pin cables captive. This means that you can largely choose which connectors you want inside your case, reducing clutter. With a choice of 12 Molex and 12 SATA cable, plus four additional 6+2-pin PCI Express cables, there’s certainly enough for even the most packed PC.

Corsair HX850

Overall, this is a fantastic PSU that you can rely on if you’re building a high-end PC. The only thing holding back from an award is the slightly-cheaper XFX Pro 850W XXX Edition, which is marginally the better buy.


Price £130
Rating ****


Size 150x180x86mm
Standard ATX
PFC active
Fans 1x 120mm bottom
Fan control automatic

Claimed Output

3.3V rail 25A
5V rail 25A
Power supply wattage 850W
SLI certified no
CrossFire certified no


Modular yes
Molex connectors 12
Floppy disk power connectors 2
SATA power connectors 12
4-pin CPU power connectors 1
8-pin CPU power connectors 1

Buying Information

Price £130
Warranty seven years RTB

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