Why do you need to change the RMx 850W if it is doing the job ? What spec is it that you are powering ?
I'd love to know this myself.
Fair enough.
That's going to be on beastly rig!
Almost every time i seen a post about coil whine it been a Corsair PSU
Don't know if this is mainly due to most people buy Corsair PSU's (Even the PC am writing this on is using one)