The Chieftec Nitro 88+ SPS-650C and the OCZ OCZ-ZS550W are the best products in this review. Both are quiet and affordable. The OCZ is just a little more expensive than the noisier and less advanced Chieftec CTG-600-80P and HIPRO whereas the Chieftec SPS-650C, being cheaper than the Antec HCG-620M, is superior to the latter in efficiency and noiselessness. Therefore, we are proud to award these two PSUs with our Recommended Buy title:
This pair of leaders has overshadowed the Chieftec A80 CTG-600-80P and Antec High Current Gamer HCG-620M which are quite good for their class, too. You may want to consider them if the better models are not available. Our main gripe about them is that they are rather noisy at high loads, although quiet at medium ones.
Antec’s EarthWatts EA-650 Platinum is let down by its fan regulation algorithm. As a result, this Platinum-certified model may only be interesting for eco-conscious users who are willing to save a few watts of power at the expense of their acoustic comfort. If you dare risk your warranty and replace the default fan with a slower one, this PSU might be far more interesting. There are no Platinum-certified PSUs in the same price category and it has no other problems save for the noisiness.
And finally, the HIPRO HP-D5201AW can hardly be recommended at all. It is the loudest at any load, has some problems with electrical parameters and is but slightly less expensive than the higher-wattage and overall better products from OCZ and Chieftec.