Note: I will have to defer to others regarding analysis of the dump files.
= = = =
Just looking at Reliability History alone:
How do you normally shutdown your system?
Did you install any new software or hardware just before or on March 22nd?
What do the technical details reveal?
Especially those blue monitor (?) icons with the green check marks. Summary =
Hardware error
I do not recognize that blue monitor icon.
Overall, I believe that the PSU is the primary suspect.
Power down, unplug, open the case.
Clean out dust and debris.
Ensure by sight and feel that all cards, connectors, RAM, and jumpers are fully and firmly in place.
Hopefully there is just a loose connection causing the shutdowns/hardware errors.
If not a loose connection then the next step would be to test the PSU.
Do you have a multi-meter and know how to use it? l Or have a family member or friend who does?
Reference:
https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158
Not a full test as the system is not under load. However any voltages out of spec are problematic.
Especially if for RAM.