Top positive review
5.0 out of 5 starsGreat power supply that you can depend on.
Reviewed in the United States on August 24, 2017
Corsair offers a wide range of power supplies, and the HX series are near the top of their quality spectrum. These are very efficient, work silent (no fan during normal operation), and overall are very good for the health of your PC in the long run. I personally purchase the HXi series for higher loads, and the competing EVGA Gold for others. HX series is in between the two, giving slightly better efficiency, trading off on size and price.
There are basically three reasons to go for a platinum PSU. First the efficiency, however this would be my last reason in practice. Then the features, like modularity, and most importantly the build quality, which affects the warranty, and of course the power quality your motherboard and other components receive. The last one is very important if you want to keep a stable working PC for a long time.
Going into details, the efficiency of 80+ Platinum PSU are peaked at 50% load, and 240V of power. To give some perspective, if you have a recent PC with an I7 or Ryzen processor (about 120W), and a decent GPU (let's say 1070 at also 120W regular 160W on load) your total load, including other peripherals will be a tad under 350W if you are not overclocking. If you get the HX750 model, you'd then be drawing about 380W from wall at 92% efficiency (with 120V). If you have the average US 12c/kWh rate for utilities, and use the PC for 8 hours of gaming a day, you'd be looking at a power bill at about $135 per year of usage. If you were to go with a 400W bronze PSU, the bill would go up to $150. That's why I don't recommend going to platinum PSU just for efficiency, but there are much better reasons. (Exceptions are if you're unfortunate to be in PG&E service zone with 45c / kWh rates, and need to use 4 GPUs for 24/7 machine learning tasks, or just crypto mining, then the bill differences would be in hundreds of dollars).
The main advantage is the quality of the parts. Most PSU will work fine under moderate load with clean power coming from the wall. However things change under heavy load and/or power issues, especially brownouts, which will not be caught the surge protector. You'd want to avoid them, hence get a more expensive PSU. One way to measure the quality is looking at the warranty length, for example this one has 10 years, which tells a lot about how much Corsair believes in them as the manufacturer.
The second advantage are the better features. Higher end PSUs, like this one will offer modularity, lots of connectors, a silent fan, and sometimes monitoring options. Believe me, modular PSUs are in a different league than the old style ones. For example I have a small PC as a router, which is cramped, but only needs a few connectors (since it only works as a basic router). Having a modular PSU saved a lot of room inside the small box. Also at the top of the line the HXi versions, which I personally prefer over the HX series, comes with a USB connector to the motherboard, which will allow you to monitor the power level of individual ports. This is very useful if you are into overclocking your system.
I have built many PCs (some upgrades, some for friends), and Corsair is one of my go-to manufacturers for PSUs. These work well, has lots of features, and have great build quality.
