shutdowns

I have my iMac (running Mojave) on a UPS. A few days ago power went out for a short while when I was away. I came back to find the iMac in the middle of a shutdown process (initiated by the UPS), but a dialog asking me to confirm quitting an application had stopped it. Fortunately, the power...

Hi I have not-so-random shutdowns problem with my 2014 Retina 27" iMac. When i try to install a fresh install of Catalina from USB onto the internal Apple SSD, first stage of the install works fine then at the installation after the first reboot when the ETA bar is shown it will reach the end...

A buddy of mine brought his MP3,1 over to show me how it randomly shuts down as if the power cord goes unplugged. It feels like it's getting worse and has trouble making it to the desktop now. Trying with multiple boot drives Lion, El Capitan, High Sierra, Mojave, Windows 7 and 10. Same result...