After 5~25 minutes of gameplay (up to 2 hours max) the game stop responding, and crashes the Display Driver.
I've opened a support case (15101602) and all required data for further analysis is attached to it.
The exact same issue is constantly being report in this thread:
https://discussions.ubisoft.com/topic/78181/pc-i-am-experiencing-frequent-crashes-freezes-in-game-post-here/1197?lang=en-US
Tried two different systems and the problem happens in both. According to the mentioned thread above, the issue can be reproduced in several areas of the game.
In my case, I'm having the crash at: East Anglia | Serpent's Landing.
Threads outside Ubisoft forums reporting the same.
Nvidia
https://www.nvidia.com/en-us/geforce/forums/geforce-graphics-cards/5/414166/assassins-creed-valhalla-crashing/
https://www.nvidia.com/en-us/geforce/forums/geforce-graphics-cards/5/425983/latest-drivers-broke-assassins-creed-valhalla/
AMD
https://www.reddit.com/r/Amd/comments/k30mp2/ac_valhalla_crashing_radeon_software/
https://forums.guru3d.com/threads/ac-valhalla-crashes-with-vega64-post-20-11-1-drivers.436765/
Tell me in case you need further information, I'm waiting Ubisoft's analysis.