Nethserver restarting in grub

Good evening, I will use the translator, if possible, please help me.

I use Nethserver 7.4.1708 on a server for local access for approximately 15 clients, with several years of use without problems

Unfortunately the server suffered electrical damage, but I managed to recover the motherboard, it worked well for a day and there was synchronization on Nextcloud, but today there were some restarts, it still displayed the shell, but now it started to go into a reboot loop in grub, no It’s a problem on the PC, it just restarts after CentOS grub

Would you have any suggestions on how to recover safely, there is a large backup collection within it?

I discovered, at first, one of the parts of the case that was preventing the HD from booting