Ubuntu 20.04 booting issue in Legion 5i

Solution 1:

BIOS

Lenovo Legion 5-15IMH05

You have BIOS version EFCN38WW.

There's a newer BIOS available, version EFCN39WW, from 14 Sep 2020, and can be downloaded here.

Note: Verify that I have the correct web page for your model #.

Note: Have good backups before updating the BIOS.

initramfs

Boot to Recovery Mode (newest kernel), Root Access, and use this command to take care of the decoding error:

sudo update-initramfs -c -k $(uname -r)

Nvidia

First, in Software & Updates, Additional Drivers tab, confirm that the nouveau video driver is selected.

Then purge all of the old Nvidia stuff with:

sudo apt-get purge *nvidia*

reboot # (reboot normally)

The current Nvidia driver for your GTX 1650 is version 450.80, and can be downloaded here or here.

Then install the 450.80 version and reboot. Verify Software & Updates, Additional Drivers tab.

Update #1:

Reinstall Ubuntu.