Here is a list of some of the symptoms that could point to a Power Supply Unit related issue on your PowerEdge server.
It's important to clearly identify all the symptoms to be able to troubleshoot efficiently afterwards.
Except for the cooling fan inside the power supply, the noise emitted by the PSU should be minimal. Any new or unusual noise, as well as a possible smell of hot plastic or other, coming from the back of the Server could indicate an issue with the Power Supply.
In the case where only one PSU is installed in the server, a symptom for PSU issues could be that the server restarts randomly without warning. Maybe it also freezes and a hard reboot is needed to get it working again.
There are different indicators on your server's PSU that you can look at to get more information. More details are provided in the PSU How-To page.
For more technical content, you can refer to our online Enterprise Knowledge base.