We had 2 instances were a customer reported that his server switched OFF automatically intermittently. The customer would switch it ON and it would switch OFF again after a few seconds or sometimes after a few hours.
The first time this occurred, we checked the Windows Event Log but it was not showing any errors, related to the power off, apart that the event log service was not stopped properly. There didn’t seem to be any BSOD either. At this stage we suspected it was a power issue. We replaced the power supply and left it on test. The problem re-occurred within a few hours.
To cut a long story short, since we had a spare server we could test different components and at the end it resulted that the culprit was the power switch.
Replacing the power switch solved the issue in both cases. The part no. is 459186-001. The part no is for a cable which includes the motherboard connector, power switch and 4 LEDs located on the front of the server. A photo of the cable is shown below.
The second time this happened it was much easier to identify the cause.
Hope this helps someone.