Ubuntu freezes after loading desktop?

Question

linux

Installed Ubuntu 18.04 on ASUS X570UD-E4038 laptop. After booting the system, after a short period of time, the system freezes tightly. I looked at the logs:

UPD:
I installed Ubuntu 16.04 as a replacement. Everything started with one BUT. It takes a very long time to turn off. Errors in logs:

Answer 1

Well, to fix MODSIGN: Couldn't get UEFI db list
, go to BIOS:
Security -> Secure Boot -> Secure Boot Mode -> [Standard]
Try also to switch to another TTY: CTRL-ALT-F1 and type:
sudo pam- auth-update
sudo service lightdm restart