Are you using frame gen? I see it’s off in the last pic.
And 1440P is more CPU limited. Not as much as 1080P, but less than 4K.
A 4K monitor running the sim in 4K would definitely increase your GPU usage.
The reason I ask is because, with frame gen on, Dev mode → Debug → Display FPS would show 70 FPS, and another display like ‘nVidia Performance Overlay’ would show 140 FPS (your frame doubled rate.)
You probably already know that, so forgive me if I’m being redundant.