I Have a hx620 from 2006/7, its been through many motherboards cpus fans vga cards and open and closed water cooling and its never missed a beat and never heard a thing from it.
I have been toying with the idea of another 290 so I just grabbed a hx1000i
(I know 850 would have done but hey) and as soon as any load was put on the cpu or graphics card (even a you tube video) the PSU had a buzzing emitting from the psu, a vibrating cap as corsair call it. I tried all things suggested on there psu forum.
some of them made me raise my eyebrows tbh, disable eist and c1e, wtf, how is that acceptable that to potentially cure an ill on the platinum power saving psu I may have to run my oc'ed cpu at full chat 24/7.....anyway made no difference
also enable vsync on card, so I cant use my dk2 then?? what about peeps with shiny new gync or upcoming freesync?? ......also didn't work
anyway I digress, I even popped it in my daughter pc, same thing so maybe its a trait of these or its duff.
TBH it wasn't a very loud buzz at all sorta like crickets off in the distance but the pc in in a very quiet room in a very quite desktop and its all I could hear.
also to note is 2 out of the 4 akaska viper fans which sit quite happy at 600rpm on a fan curve had coil whine from hell with any rpm below 1100 rpm so its winging its way back from where'st it came and im back to golden silence with the trusty old hx620 for now.
think I'm gonna give an evga p2 1000 or g2 850 a try