iMac random shut down and restarts. Sonoma 14.4.1 Fixed !

Random shut downs and restarts. w/no chime either. Tried various mechanical unpluggings

and delayed restarts w no improvement until ...I reset the PRAM. and this has eliminated the irritation for now.

Was going to re-install start up disc w 14.4.1 again, but this PRAM reset is holding.. Very loud and solid startup Chime too.