OK I've just connected this PSU a few mins ago.
First thoughts.
BLOODY hell it is SILENT!!! I've been buying PSU's for 10 years reading "silent" badged everywhere yet when I turn them on, its all I hear (Have not 100% tested this to be the GFX card, but pretty sure).
I'm not pretending to be some hardcore PC builder but I have built PC's for 10 years now and I have to say so far it is SILENT.
ALSO, I am using a new case Coolermaster RC-1100 Cosmos S "Sport" so that may have contributed. But that thing has open vents all over it.
Perhaps not the best of posts since I just got the PC on and am happy at the moment, if you have questions, ask. I bought the AX750
One thing to note: the 24-pin connector is as you would expect but the other end is split into 2 connectors, very strange, and made me think what was going on. Basically plug it into both far left of the PSU. I stress you need BOTH connected.
It threw me off, so might do the same to others.
Great service from OcUK as usual. I just hope this PSU doesn't brake like the last Corsair PSU did, also bought from OcUK
http://www.overclockers.co.uk/showproduct.php?prodid=CA-156-CM&groupid=701&catid=7&subcat=29