Act 2 unplayable performance wise (FPS to 5)

Hi all,

So I've been experiencing FPS drops in act 1 which were manageable. Usually I could stay between 60-80 FPS on high settings, 1440p.

I just finished act 1 and started act 2. There is a huge difference in performance in act 2! Even when fighting small monster packs my FPS immediately drops to 20 FPS and I had to fight Rathbreaker on 5 FPS which was impossible. The only reason why I beat him was because I deal a lot of damage over time.

I cannot understand the difference in performance as I was fighting big monster packs in act 1 already and was able to keep a stable FPS.

Is anyone else experiencing this? :(

By the way, changing the settings to low made no difference.

My specs are:
RTX 2080 TI
RYZEN 7 5800X
32 GB RAM
2 TB SSD (running game from SSD).

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