I can’t find any streaming settings within the battlernet launcher, though i could have sworn i disabled them a few years ago as i don’t stream myself.
I’ve used the DDU tool to reinstall my nvida drivers cleanly already. I have now done it a second time as per your request.
the Nvidia control panel power management is set to Prefer Maximum Performance and applied the changes.
My Control Panel -> Power Options are set to High Performance.
Nothign is plugged into the onboard graphics ports just a single monitory connected to the gtx970 card.
I tend to run very few background processes, but i will try that tonight or tomorrow and reply with the results.
Currently still stable on dx11 legacy. Will test again dx11/12 with the selective startup.