Here goes an update...
I have been redoing my OC in BIOS starting from default settings... well, spent a lot of time at default settings...
Luxmark.exe was crashing with the nvlddmkm event all the time...
Just could not commprehend - RB benchmark is passing, 3DMark FireStrike is passing at every level, even the new Superposition has passed with no issues... then RB stresstest is crashing again...
Start thinking that this can not be a hardware error... something is messing up RB - so started to kill applications running in the background...
And I have found something:
STUPID GPU TWEAK II!!! Two Asus (related) softwares don't play nice with each other on an Asus board...
Well, before I noticed the RB stress-crashing problem, I have set GPU Tweak II to start with the OS, minimized to be available if needed... I've had a custom fan curve setup, more aggressive than its default - and it was doing it job as shown with other benchmarks...
If I set GPU Tweak II to open only when I click on it, set the max fan speed (tried only this), then close it - the fans will keep the setting, and RB stresstest will go on for at least one hour (the max I had time to try) without problems! :cool:
Edit: I never used OSD on this system...