I have a Seasonic X650 gold. Its completely silent (fan is variable and never runs in my case) and one the highest quality units out there. Better than everything listed here so far (although other options are good too).
There is a difference between quiet and silent, btw.
1000 RPM fans are quiet, but not silent.
I have 120mm fans that run at 2000+ and even that is not what I would qualify as loud.
I think that our two contrasting statements/opinions, illustrates the point that people perceive noise differently. But surely if someone wants a quiet unit then they want to reduce fan speed as much as possible, and truly quiet PSUs have much lower idle speeds than 1000RPM.
CoolerMaster GX 650W is also another solid candidate.
No it is not. I've seen reviews where the idle speed was shown as 1000 or 1100RPM.
Enermax Platinum series all the ones I have tried are Pretty quiet, and Seasonic Platinum Rated series is what Im currently using in my two main machines. Just very good ball bearing and they have those vibration dampeners on the fan inside the power supply good stuff.