Our load tests utilize a couple of FAST ATE active load testers and a variety of other equipment such as an oscilloscope, power conditioner, temperature probe and a power consumption meter. You can read more about our standard testing approach here.
The tests performed are based around six conceivable setups that are out there and progressively load down the PSU up to the power supply's limits or 1000W, whichever comes first. Since our test equipment's limits are lower than that of the Corsair HX1050, we can only test it to 1000W.
Voltage regulation for the HX1050 was very good. Our tests showed that the 12V rail managed to stay within .5% of the ATX specification of 12 Volts. The two minor rails did quite well too. Both the 3.3V and 5V rails managed to stay within 2% regulation from start to finish. The HX1050 couldn't have done much better.
The DC output quality wasn't quite as spectacular as we would have liked to have seen with the HX1050, but it was well within the ATX specifications and nowhere near the range where we start getting concerned. Starting off with Test 1, we witnessed a ripple of 14mV peak to peak on the oscilloscope. This steadily increased as we progressed through the tests and bumped up the loads. By Test 3 we were seeing nearly 30mV of ripple on the 12V rail. This maxed out at 41mV by the time we reached our final test.
We were very surprised by the efficiency of the HX1050. As the unit is rated for 80Plus Silver efficiency, we weren't expecting to see nearly Gold efficiency. Keep in mind that 80Plus Silver requires 85%/88%/85% efficiency at 20%/50%/100% loads and Gold requires 87%/90%/87% at the same loads. As you can see from the results, the power supply manages to pull Gold efficiency until at the very end when it barely dips into the Silver range.
While we don't have the equipment to fully test the Corsair HX1050, there are several conclusions that it is safe to say about the HX1050. Given the results that are shown above, there is no reason that the Corsair HX1050 would have failed any of our tests. The results shown above are all well within specifications and we were only 50W shy of being able to fully load down the power supply.
Corsair has done a spectacular job with the introduction of the HX1050 into the Professional Series of power supplies. The HX1050 shows improvement in absolutely every area to make it worthy of replacing the HX1000. Voltage regulation was very good across the board from start to finish. While the DC output quality wasn't the best we have seen from Corsair, it certainly is good enough for almost any enthusiast grade system.
Corsair also took a huge leap forward with the increased efficiency seen in the HX1050 and the extra two years of warranty. Corsair adds a bit more to sweeten the deal by offering the HX1050 for $219 which is the same price as the older and much less efficient HX1000.