Application Unity.exe has been blocked from accessing Graphics hardware

Hello,
recently I started to get black screens when working with Unity 2018, the display driver is crashing without recovering, so I've been forced to restart the computer manually, then I get this error message:
"display driver stopped working"
I've noticed this problem when using some heavy rendering like particle systems and 'Enviro Sky' clouds with rain. It happened also two times without using such a demanding graphics processing.
I was playing the latest Doom, Prey and Witcher at maximum graphics settings just to see whether it is the graphics card, but these games just run fine for hours....
Recently I started to get also this error after the restart:
"Application Unity.exe has been blocked from accessing Graphics hardware"
I tried some fixes in the web like "TDR delay registry fix" and running the sfc /scannow from cmd(which resulted with no errors) and nothing seems to resolve the problem...
Please, help...

 

What graphics hardware are you using, and what driver version? It sounds like a hardware or driver issue.

 

It is an evga GTX 1080 on a Dell Precision T5600 dual Xeon cpu motherboard
driver version: 23.21.13.9135
I updated the drivers - complete uninstall then reinstall them again, but problem still exist...
Could it be some incompatibility with the motherboard?