Lower your game's resolution (e.g., from 1080p to 720p). If your FPS does not increase, your CPU is at its limit and cannot process more frames.
Software overhead can steal valuable CPU cycles from your games. Fix CPU Bottlenecking & Optimize CPU For Gaming...
Frequent stutters or "micro-stuttering" (low 1% frame lows) are classic signs that the CPU is struggling to handle game logic or background tasks. 2. Optimizing Windows for CPU Performance Lower your game's resolution (e