HP DL360 power supply have different firmware and coupled with that the PDU supplying power tripped. Could different power supply firmware cause this

So, after bringing a third system into the mix, and experiencing the same issue, we began to question the environment. I dug up a copy of the HP ProLiant Servers Troubleshooting Guide and found the POST problems flowchart shown below.

Carefully running through the steps in the chart, we realized that the one constant across all of the servers was a KVM switch attached to the data center crash cart. This was a consumer-class USB-enabled KVM. As per the highlighted node in the flowchart, Do you have known good KVM?, I could not answer conclusively.

So, we unplugged the servers from the KVM switch and ran an automated boot, sleep 300; reboot sequence in rc.local. The servers had no issues with this, regardless of the normal DIMM, low-voltage DIMMs, PSU wattage, etc.

This was all the result of a poor interaction with a USB KVM switch. By virtue that this was the console, it ensured we'd see the failure if we were looking for it. Self-fulfilling...

When you replaced the bad power supply with a known-good power supply, you should have had a green light on the new power supply. Have you verified that utility and UPS power are okay?

You can check your operating system's logs to understand what the server thinks is wrong. Specifically, the HP IML log will tell you what's up. You can also get this information if you reboot and watch the POST messages.

Which operating system are you using?