Question PC shut's down every 30 minutes

[mamaliga24]

Hello !!
I have my PC for some time, and suddenly started to shut down after every 30 min, on the clock, after staying unused for several months.
I checked the following:

• Power supply (changed with a new one, same problem)
• RAM memory (checked every slot and every RAM card individualy, the RAM cards work, but the problem persist)
• Graphics card and processor (even changed the thermal paste, i thought it would be the temperature, but same problem)
• Made an wire management, automatically checked every pin and every connection on the Mobo, nothing was wrong
• Checked the HDD and the SSD
• Reinstalled the Windows several times, different types of versions, even tried Linux, same problem
• I tried to update the BIOS, same problem, it restarts even when i'm in BIOS
• Checked with several methods in finding any malware or a virus, nothing
• Checked the power management from windows settings, but the settings are ok

I tried almost every method found on the whole internet, but not succeded. Visually, the MOBO looks ok, doesn't look like having any capacitor "exloded", but something, not software, but hardware, i think it commands it to shut down.
Can u help me with some ideas please guys?
Thanks a lot, God bless you !
Mobo:

https://imgur.com/u7Rk4wB

View: https://imgur.com/u7Rk4wB

CPU:

https://imgur.com/tYp3O3T

View: https://imgur.com/tYp3O3T

GPU:

https://imgur.com/pEd0Mb3

View: https://imgur.com/pEd0Mb3

 

[Koekieezz]

PSU? Mobo?