Boot-Loop after choosing os in grub

after entering my password and choosing the OS in grub it will simply reboot and ask me to enter my password again (see video)
What could have possibly caused the issue? idk, as far as I am aware I just upgraded my system a few days ago and since then it did not boot. It is NOT the grub-issue from august. I’ve also experienced problems with a full disk (because I didn’t clear pacman cache for waaay to long) which is also not the problem atm

What have I tried?
chrooting into my installation and running

grub-mkconfig -o /boot/grub/grub.cfg
mkinitcpio -P

Also upgrading my system and rerunning those commands did not help.
My laptop is running UEFI and it’s the model HP 17-ak013ng if that helps…
What is (causing) the problem leading to a boot loop and how can I fix it?

you get an MCE error , this means “Machine Check Exceptions”

could be a loose RAM Module also…

I feel kind emberassed for not seeing those myself…

So I installed rasdaemon acoorsing to arch wiki and enabled it, however it did not log anything to journalctl

When trying the ras-mc-ctl command I got an error, as referenced in this github issue

Frustrated I screwd the laptop open. I didn’t see anything out of place so I temporarly took out the bios battery to reset the bios. Now endeavouros does not show me any mce’s, but is stuck while booting. Sadly the same is true for my “rescue” usb-stick with lubuntu… Wish me luck to get any os working here

(picture at what point it’s stuck, but I guess I’m on my own now. Thanks for the help <3 )