I have a Rosewill Hive 650 and I noticed today that there is a low level High pitched noise (similar to what CRT tv's produce if you ever heard it from them) coming from it. When I realized that was where the noise was coming from I flipped the power switch on the psu and it stopped and when I flipped it back on it returned.
Is this a sign of potential failure? Is it something I should worry about? I know better than to open it as I have next to 0 experience with electrical work and that some units within it still carry charge even when powered off.
I would RMA it if possible, it's okay for power supplies to make some noise when turned on but when you turn off the computer there should be 0 noise without having to switch it off. Try another power outlet in the house before RMA'ing it. I have owned around 5 power supplies (all my own builds) and not a single one ever made a noise when turned off.
Edit: I recall helping someone out with the same issue, try using another power cord (the cord that connects the power supply to the wall), that seemed to help that person in his case.
I have since ran my pc since then for a few hours a couple of times and turned it off and have not had it happen again, is coil whine a major issue or more of an annoyance? I have had this unit for almost a year now so I doubt I can RMA it.