Completely modular, can be literally inaudible.
Seasonic has long held a reputation for producing great quality power supplies, and the X-750 certainly holds this up. Even just looking at the price suggests a level of quality that most manufacturers rarely reach - at $245, it's over $100 more expensive than competing brands at the same wattage, and amusingly there are even some 750W power supplies for sale at only $75 (most likely with the largest 5V rail you've ever seen!).
The X-750 is really in a class all its own though, and with an 80 Plus Gold certification thanks to the expensive components used within. It's not overly heavy, but certainly has a heft to it that you definitely want in a PSU - and the 100 per cent modular cables, ranging from the 24-pin all the way to the smallest molex cable are sure to impress. While they don't really all need to be modular, it can be handy in some cases, and certainly ain't gonna hurt it none.
Cooled by a large 120mm fan, this model is unique in that the fan will only actually start spinning when the PSU hits a certain temperature. While this is sometimes unsettling, it did kick in after about five minutes, and at desktop idle was completely still, resulting in absolutely no noise generation. As seen in the Cougar review above, the test settings gave the single 12V rail rated at 62A an idle reading of 12.124V that wavered slightly to 12.351V, but remained rock solid under load. The 5V rail was similarly impressive, moving from 5.023V to 5.020V.
The fan control is certainly impressive, though it did result in the PSU getting slightly warmer than usual - and when left idling overnight, it was pretty toasty all over. With pricing making matters somewhat awkward, we definitely recommend this PSU for a low-noise build, but gamers can just as easily look elsewhere for cheaper.