hi,

when I arrived in novigrad there is a quest you can do and you must help a blacksmith to redo his profession
first helping him to get resources by talking for a deal then ask that bodyguard to stay help but the bodyguard requests
another favor and so you must destroy or speak and make a deal with someone on the boat.

I did no have enough magic skill to charm the npc so I had to destroy the barrels,
2 barrels to destroy .
It is like the physx or something calculated and required alot of performance got to from 30fps to 1 for a few seconds
but thats not all it kept freezing the entire time for 5-10seconds and then I could move again for 1-2 seconds.

So thats how i finished the quest by running away from on the deck of the ship towards the wooden docking area towards the bay of the town with the scene freezes when i was back in town nearby and closer to the houses away from the ship everything was back to normal.
(even tried putting everything on low and on 1000 resolution didnt fix it)

I got a gtx560 playing the game fine on 25-50 only that part was immense costly probably a bug or something or x?