my pc keeps shutting down after login or sometimes at login

[JustSolo]

every time i turn on my pc , it turns on normally till the login screen , when entering the password (sometime even before it) just powers off( no blue screen ) like straight up power off,

 

before this the pc was shutting off randomly? (not sure as it sometimes powers off when opening whats app or chrome but i may be wrong) , so i checked the temps which was like 97'C on load so i re applyed thermal paste and it was back on 50'C and for a week or so everything was fine , and then windows was powering off when i just glimps the login screen( i had no password at that time)so after trying a lot of different fixes and failing even getting a corrupt bios error and booting from the backup bios , i reinstalled a fresh  windows 10  and it had  no problom during installation and after installing  or when i downloaded (chrome,firefox,vlc, office 2021 etc) and updated windows to latest update , and at first it worked ok and then this login error started.

 

so i went screw windows and tryed to install manjaro but when i was booting the installation media it also shuts off just as the login screen appeared.

 

PS- i also have the photes  of the errors when pc was randomly shuting down and the bios error

 

my pc specs :-

i5-2400

gigabyte GA-H61M-S2P-R3 motherboard 

CRUCIAL 8GB ram (1333mhz)

zebion 450W ECO-2

WD green 256 GB ssd

tosiba 500 GB HDD( was unplugged)

[jaslion]

I mean your nuke of a psu isnt helping at all.

 

This sounds like a psu shuts off because it cant handle power draw issue

[podkall]

17 minutes ago, jaslion said:

I mean your nuke of a psu isnt helping at all.

 

This sounds like a psu shuts off because it cant handle power draw issue

that PSU has 18A 12V rail, when I looked at similarly W PSU that has high quality it almost had double that amount