Computer shuts down randomly by OS

Bingo0904 · April 2, 2023

I have never experienced a computer shutting down on its own showing the "shutting down" screen. I am able to boot to windows and then randomly the computer will shut itself down by "shutting down" screen. It will shut down and then restart by itself and fail to power on. However, when pressing the power button it will boot to windows. There is no predictable time for how long I am able to stay on desk top screen idle. Yesterday the computer did not shut down for 5 hours. Today it shuts down "shutting down" after a few minutes. If something wasnt saved while the computer is shutting down, it will give me a notice to save the process, allowing me to cancel the shut down.. after I try to cancel the shut down.. a few times... the computer will shut off without warning. What could be causing the problem?

Here is what i already tried:

Replaced the powersupply

Cleaned dust around parts and the case

Replaced the thermal paste

Tested each ram stick (and cleaned)

Reseated the CPU

Checked the temperature of the CPU (21-30 C)

Reseated the GPU, removed it to see if its the problem

Checked for any loose wires, bulging capacitors, reset the CMOS battery

Accessed event viewer: There was no critical alerts

Run safe mod (still shuts down)

Run BIOS (able to access bios but shuts down randomly)