System not be able to enter suspend mode

For a few days, the system has not been able to enter suspend mode. Could someone give me some advice on where to start looking?

Screens (2) goes completely blank, the cursor on the up left side blinking, and the only solution is turn off the computer.

My version is 20.04

Inxi output:

Graphics: Device-1: NVIDIA driver: nvidia v: 495.29.05 
Display: x11 server: X.Org 1.20.13 
driver: nvidia unloaded: fbdev,modesetting,nouveau,vesa    
resolution: 3840x2160~60Hz, 1920x1080~60Hz 
OpenGL: renderer: NVIDIA GeForce RTX 3070/PCIe/SSE2 v: 4.6.0 NVIDIA 495.29.05 

Thank you

Since devices are more and specific to the Windows OS and the native binary NVIDIA driver mediocre at best you might have chance to make the acpi parts needed by nvidia get running again. Here is a pretty detailed explanation.

Basically you should try to tell a part of the firmware, that you are "window" device.

Open a terminal and type:

sudo nano /etc/default/grub

There is a line that starts with: GRUB_CMDLINE_LINUX_DEFAULT="...."

(The dots mean that there might be an entry inside) Add the following definition:

acpi_osi=\"Windows 2015\"

into that line so it looks like this: (do not overwrite entries, just add)

GRUB_CMDLINE_LINUX_DEFAULT="acpi_osi=\"Windows 2015\""

close the editor with keyboard keys Crtl+x (thats how nano works) and issue the command

sudo update-grub

reboot

If it doesn't help or you've got problems after restart: simply repeat the steps above and remove the entry, save the file and call update-grubagain - so no harm is done.

Good luck