The Tech Report has taken a look at 11 PSUs in the 500-750W range. This includes PSUs from Antec, Cooler Master, Corsair, Enermax, OCZ, PCP&C, Seasonic and Thermaltake.
Among the units we'll be looking at today, PC Power & Cooling's Silencer packs the most grunt at 750W. 500W models from Antec and Seasonic round out the low end of the wattage spectrum, with everyone else falling into place between those extremes. A higher wattage rating doesn't necessarily guarantee quality, though. We've designed our test suite to ensure lower-wattage models aren't penalized for bringing fewer watts to the table.
Wattage ratings determine how much power a system can squeeze from a PSU, but a power supply's actual socket draw is often much higher. This discrepancy is caused by inefficiencies in the power supply's conversion of AC to DC power. Some do a better job than others, and the industry has come up with an "80 Plus" moniker to denote PSUs that are at least 80% efficient. Only about half of the power supplies in this group have an 80 Plus rating. Interestingly, some of the PSUs that lack the 80 Plus logo still come with claimed efficiency ratings of over 80%. We'll be testing efficiency ourselves, so we can see whether the 80 Plus-certified units really are more efficient.
Check it out over here. Two power supplies received an editor's choice award: the Corsair HX 620W and the PC Power & Cooling Silencer 750W.