Hi @nafonso, welcome to the NVIDIA developer forums.
Do you mean this pop-up?
Well, disable the overlay in the GeForce Experience settings. Or simply don’t run GFE in the first place?
The internal hooks of GFE how it decides to show this notification are proprietary, so I can’t share that with you. Generally speaking it will be triggered by any app or game that does a certain set of GPU initialization calls either explicitly or implicitly through OS system calls. Why Blender does not trigger this I don’t know.
For more questions on GeForce Experience I recommend our dedicated forums.
I hope this helps!