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 AX1200i, we can only test it to 1000W.
Let's start by taking a look at the voltages to see how well this unit did during testing. Starting with the 12V rail, we see 1% regulation from start to finish. The 12V rail showed a total drop of .10V from start to finish. The 5V rail did just as well as it managed to stay within 1% of specification with a total drop of .06V from start to finish. Moving towards the 3.3V rail, we see that regulation was still within 1% with a total voltage drop of .05V.
DC output quality was what were hoping for and even better than the previous AX1200. We started off seeing 4mV of ripple on the 12V rail during Test 1. As we increased the loads, the ripple had increased to 9mV at a little under half load. By the time we had the maximum load of 1000W we were seeing 14mV of noise.
The Corsair AX1200i is rated for 80Plus Platinum efficiency which is a step up from the previous rating of Gold for the original AX1200 unit. This means that the power supply must perform at 90%/92%/89% efficiency at 20%/50%/100% loads respectively. As you can see, the Corsair AX1200i passed on our bench wasn't close to failing at any point.
One thing is very clear when you start to look at the new AX1200i and that is we can't simply judge it based upon performance and build quality. The integration of the unit into the Corsair Link hardware and software represents a huge shift in what enthusiasts are going to want and be able to do with their power supplies. As such, we have to take a look at both pieces separately and then again as a whole.
Looking at the performance of the AX1200i, we simply can't find enough things to say about the unit. Voltage regulation was the best we have ever seen in any power supply. We've had other units that would have one or more rails perform within 1% of specifications, but never all the rails on the power supply. It is simply unheard of and Corsair has done an amazing job with this. It doesn't stop there though as the DC output quality is also the best that we have ever seen. We wouldn't be nearly as shocked and surprised if this was a mid-range unit pumping out 700W or so, but keeping the noise down so low on a 1200W unit is amazing. The AX1200i is also at the top of our list for efficiency. The last year and a half has shown a surge in Platinum rated power supplies, but the number of them that can output over 1000W can still be counted on your fingers.
The build quality of the AX1200i is also superb. As you would expect, the power supply features 100% Japanese capacitors throughout. Another big piece of the puzzle is that Corsair is confident enough to back the power supply by their industry leading seven year warranty. To the best of our knowledge, Thermaltake is the only other manufacturer to offer such a warranty and it really goes to show the confidence that Corsair has in the AX1200i. The inclusion of the DSP is also a big step and you can bet that many others will be following suit soon and are now a little behind the curve.
Set all of that aside and look at what the integration of the AX1200i into Corsair Link means for the end user. No longer are you stuck with a fan you can't control or a fan that requires a rheostat of some sort to manage. Those that are conscious about their power consumption will now be able to tell when and where it is going. This isn't just a built in Kill-a-Watt, but you can see which connector on the power supply is drawing how much power. You can also manage OCP on individual lines. Afraid that the volt-mod on your GPU might short out and kill your whole system? No problem!
Previously the Corsair Link system was more about monitoring temperatures with fan and lighting control. Corsair has changed that quite a bit with the addition of AX1200i and the new Dominator Platinum memory. It offers a complete system for monitoring your PC and controlling other items. Add in other items from Corsair and you've got a setup for unprecedented monitoring and control over your PC that goes far beyond fan and lighting control. The performance and build quality alone make this the best power supply that we've ever had the pleasure of putting on our test bench, but the integration of the power supply into the Corsair Link system make it the best power supply we've ever seen.