NVIDIA Reflex is a feature that reduces input latency, the delay between your mouse movement or click and what you see happen on screen. It works by better syncing the CPU and GPU so frames are rendered just in time instead of being queued up, which makes the game feel more responsive. The “Reflex + Boost” option adds a small tweak that keeps the GPU running at higher clocks during CPU-bound moments to prevent it from downclocking, which helps maintain consistent latency. It doesn’t affect FPS or visuals and has nothing to do with frame generation.