Consistent stuttering and frame drop in cutscenes and gameplay

I bought this game on Steam. The game consistently stutters and drops frames during both gameplay and cutscenes. 

The stuttering seems to happen when a new area is loaded. The average framerate I get with my settings is 90 fps but during drops, the rate goes as low as 17 fps. 

Both CPU and GPU drop in usage at the time of stuttering. Also during non-stutter instances, both the GPU and CPU do not seem to reach 100% usage (stays in 30-70%) 

My system config is as below, I do not have any background apps open. 

Game settings 

Attached screenshots

Things I tried

- Set high performance preset in Nvidia and Windows settings

- Cleared all background apps

- Disabled Gamebar, origin, and steam in-game services

- Updated all drivers

- Used Geforce suggested settings

Config

CPU - Intel i5 10400f

GPU - Nvidia 3080

RAM - 16 GB

Game running on SSD

PSU - 650W (does not draw above 450w system power)

The game is great, but constant stuttering has dampened the experience. My non-techy sister (who I play this with) also taunted me about having a high-end pc but ending up lagging. 

Someone please help me out, I can't even refund.