Problem of no signal after sleep screen Iiyama, with Linux Solus

Problem with my new screen iiyama 31.5" G-Master GB 3271 QSUB1

The screen starts up well with the computer.
Sometimes, in operation, rarely, there is briefly (one or 2 seconds) a loss of signal (black screen) and it comes back.

→ if the screen goes to sleep or if the screen is stopped by its switch off button, then afterwards it is impossible to find again the image, there is a loss of signal and the screen does not come back (no signal), it remains black,

(my old screen still work normally with this computer)

Computer, with :

  • SOLUS 4,3 fortitude
  • Asus Geforce GT 1030 LP 2 GB graphic card
  • connected via hdmi
  • Native Linux card driver (I change after to nvidia)
  • Screen was 144 Hz and 2560x1440 (same problem with 60 or 90 Hz)
  • Motherboard: Gigabyte B450 AORUS PRO
  • OS : Linux-x86_64 – nvidia driver version : 470.94 – server vendor : 1.20.14 - (with standard settings in « nividia X server settings » panel)

Connecting the screen to other computers with other systems works normally:
A old laptop with Win7
A tower computer with Win10 or Mint (older graphic card)
They all have Nvidia drivers
Linux Mint has Nvidia-driver-390 (version 390.144-Oubuntu 0.20.04.1 – Metapackage)

So the problem is not the screen.

Then, I Switch Solus to the Nvidia driver installable via DoFlicky,

I restart the computer, it works, but same problem ( when I shut down the iiyama screen it’s impossible to find back the picture (no signal, screen remain black).

Maybe the tearing during long scrolling disappears with ne nvidia driver.

When my 2 screens are in cloning mode (mirror), when I switch off the iiyama, it comes back to life atter switch on.
But when I put the iiyama in the single mode, ti doesn’t come back after switch off.

What to do?
I have seen other threads with similar problems, but not for Solus, I don’t know.
Thanks a lot for helps.