"Previous fan failure" alert

In an older thread, I asked for advice about a power supply failure in my 7010 MT.

https://www.dell.com/community/Optiplex-Desktops/Replacing-an-OptiPlex-7010-MT/m-p/7827758#M49427

I finally replaced the power supply with a EVGA 500W without problem.

A couple of days later, after several shutdowns and restarts, I got an alert "Previous fan failure" and pressed F1 to continue. I checked and all the fans were running. I downloaded Core Temp, and the CPU temps were fine.

I then shut down and restarted, and there was no longer an alert. I restarted again and press F12 to run the diagnostics. Everything passed, and the Events Log had no entry.

What could have caused the first alert? Should I be concerned?

Thanks.