...at least for me and others
I play in full screen with max settings except motion blur and on SSAO, GTx970
Go to the witcher link on desktop and right click/ properties, make sure to enable these settings like in the pic marked red

Maybe it helsp you- i had no single crash, since i h´ve done it for the last 2 Gaming sessions (a´4 hours- yes... it was a bit long :-)

reg.
Kobra

I'll give it a shot. Thanks!

hmm, crashes which i can confirm happen to me alot, when
i got my firefox open in the background..
Dunno if this is a special problem just for me, or if it is a problem with
firefox or some addon i've installed.
Could reproduce one crash, when i searched the room of tamara at the
Bloody Barons Castle, everytime i picked up the Letter and wanted to read it
in the inventory while my Firefox was open, screen went black and Witcher 3 crashed(or hung up,
so i needed to kill Witcher 3 in the task-Manager).

Happened really often to me.

I've tried and it did not help, but thanks for the info anyhow :)

I'm having crashes to desktop (2500K-560Ti-8GB RAM) without any error. But when I use DDU to erase my drivers and then install them again I don't have crashes, but after a PC reboot it starts crashing again.

Rollback to 350.12 (GTA V ready), latest driver crashing even while PC idle.