Hardware is not under 100% usage though I can't get stable framerate

Greetings,

I'm looking for advice as why the usage of my ressources stay low ~50% although I don't get framerate cap.

Here's the computer specs:

• Dell Precision 7750 workstation
  
• Core i9-10885H
  
• Nvidia Quadro RTX 4000 v461.40
  
• M2 disk
  

I tried the game (Drakengard 3 NPUB31251 1.01) in 1080p, 1440p, 2160p without much change.

I checked the SPURS config is set to unlimited. Most of the settings are by default with the latest version, I applied the 60 FPS patch and Resolution Scale Threshold to 512 as instructed in the game page.

Here's a capture of the game running with the graphs:



Any ideas why I can't get more stable performance?