For testing power supplies, I use a SunMoon power supply tester. Essentially, it's a machine made to put up to 10 different static loads on up to 10 different rails at one time. I put a load on the main ATX (labeled "12V1" in the below table,) a load on the PCI-e connector on what is supposedly "12V2" and a load on what is supposedly "12V3" as well as a load on the 3.3V and 5V via the main ATX connector. A load of 0.5A is maintained on the -12V during all tests and a load of 2A is applied to the +5VSB during all tests.

     The first test is done with the power supply sitting in an open case, almost at room temperature. So the results of the "room temperature" load tests are...

     There was a buzzing noise and the 120MM fan became very noticeable by test 4. Probably a transformer and likely an isolated incident. Often I'll have a PSU that buzzes, but a sample later on after the review has been published will reveal no buzz at all.

     During crossload, the power supply continued to buzz, but even with a 3A load on the 3.3V rail and a 4A load on the 5V rail, with 13A on each 12V rail, the 12V rails hung in with 11.98, 11.96 and 11.95V. The demand on the PSU was still great, at 512.6W, so the fan was still spinning full tilt. But after I took the load off of the PSU and brought it back down to test 1's 123.1W load, it only took 15 seconds for the fan to spin back down to it's initial low RPM.

     The voltages were pretty solid, dropping only .12V across the tests. Same as the HX620W. The efficiency was lower during test 1, but the unit ran cooler. Not sure why the temps were so much lower on the HX520W as I didn't hear the fan spin any faster than it did in the HX620W.

     Now for the hot box...

     The "hot box" is nothing more than the power supply running in a sealed up Ultra Wizard case. Only the side panel CPU vent has been replaced with an intake hose and an 80MM intake fan. On the other end of the hose is the exhaust of the load tester.

     Overall, the hot box proved uneventful for the HX520W. The only change between our two tables is the intake and exhaust temperatures.

     This time, I could hear the fan by test 3, and the results of the higher RPM's can be seen by looking at the intake and exhaust temperatures during test 3. The air coming out of the load tester is hotter, but the power supply is moving so much air, much more than what the load tester is pumping into the case, that the intake temperature of the power supply isn't any higher than it was during test two.

     After test five ran for 15 minutes, I took my measurements and bumped the load back down to test 1. I listened to the fan and counted the seconds on my watch. At 45 seconds, you could hear the fan wind down. At one minute is was nearly silent again.

     Now let's use the oscilloscope to figure out how much ripple we have.

     Ripple is measured at the load by an USB Instruments Stingray DS1M12 . Instead of using the Stingray with probes to measure ripple, I actually use the Stingray as a medium between the data being spit out by the SunMoon load tester and my laptop. Each change in voltage is collected and reported every .2ms. The time divide on the graphs is 2ms (every square being 2ms) The voltage scale on the graph is .05V, or 50mV.

Corsair HX520W	+3.3V	+5V	+12V1	+12V2	+12V3
Test 1
Test 2
Test 3
Test 4
Test 5

     Not too bad, although there was a honky tonk badonkadonk in the 12V rail. Fortunately, the most the rail ever dropped was .03V (30mV) and overall ripple was not more than .05V (50mV.)

     Let's take the top back off and see how she looks inside...

     Inside, the HX520W looks almost identical to the HX620W except this unit has a Nippon Chemi-Con primary cap instead of the Hitachi we saw in the HX620W.

     Now let's grade this thing....

     Performance (weight of 40%) gets a 9. Just like the 620W version, it's efficient, has active PFC and the voltage only dropped .12 for me overall. Unfortunately, I had to whack a half a point away for the buzzing noise and loud fan.

     Aesthetics (weight of 10%) is 9. Hey, I like yellow. In fact, if I ever had the money I'd buy myself a screaming yellow VW GTi. Of course, the sleeves on the main power cables looked great and the ribbon-style modular cables make this power supply and your whole computer look super clean.

     Value (weight of 30%) score is a 9. At a $119 retail price, I really think Corsair priced this power supply too cheap. Yes, there are power supplies with more power for less money, and I just reviewed a Silverstone that had as much power that was even more efficient for even less money. But this power supply is modular and just looks slick.

     For functionality (weight of 20%,) I'm giving this power supply a 9.5. The Corsair is modular, compact and has nice cables. No... I'm not going to whack a half point for shorting us a couple cables. There's still plenty to go around.

     Overall, that calculates to a score of "9" Once again there were only a few minor "flaws." But for $119 it's hard to complain. So without a doubt, we have another power supply that's earned a "jonnyGURU Recommended" logo:

SUMMARY:

     With the two power supply efforts we've seen put forth by Corsair, it certainly seems as if they're a company that plans on sticking around in the power supply segment of the market. This one wasn't as powerful as the last, and was a little noisier and short on a couple cables... but it only costs $119 and that's a heck of a value for the features this power supply has. Typical 80% efficiency, active power factor correction and modular cables!

The Good....

• Solid rails
• Very efficient
• Active PFC
• Modular
• Nice cables
• Compact size

The Bad....

• Again, the two separate fixed cables for 4-pin and 8-pin +12V connectors

The Mediocre....

• Mix-match of cables (sleeved main cables, ribbon-type peripheral cables)