Summary: I chose this based off the success I had with a Corsair PSU I purchased off a friend which ran well, looked good, and did it's job without trouble or coil whine. This one has thus far done the same and I will heartily recommend Corsair PSUs in the future.
Pros: Solid build quality, Good looks, Very quiet, Modular
Summary: this power supply is the first modular power supply I have owned, and it is quiet, and the cables are nicely sleeved in black however the cables themselves aren't individually wrapped. would definitely recommend this to anyone.
Summary: I bought the HX650 during Christmas. From day 1 it squealed and whined, so much so that I had to stop using my PC after a while because the noise was so aggravating. I asked for a replacement which I received the day after. Not 5 minutes after installing it, the brand new unit was squealing and whining just as loudly as the previous one. This is supposed to be a high end power supply but it's a shoddy product. Not sure how else to describe it.
Pros: -It powers your PC like a power supply should.
Cons: -It makes high pitched noises at random intervals. Seems the coils are defective (I received 2 units with the same issue). They squeal and whine rather loudly.
Summary: I bought one of these units and for months could hear a strange chirping sound. I had thought it was a problem with my water-cooling system until I did some research online. The problem was caused by the algorithm Corsair used to govern the speed up and slow down of the fan during load. They way they implemented it caused the very annoying noise from the fans. This problem has now been solved.
Summary: I have always loved Corsair products, especially their power supplies. They are (usually) built with quality parts and the fact that they have AMAZING warranty and customer support is the real thing that brings me back. Unfortunately, their HX line (HX650, HX750, HX850) is plagued with many problems. The most experienced problem is the infamous 'chirping fan'.