What are DLSS and FSR? How upscaling gives you more FPS

Your screen

Upscaler mode

Stretch method

Game draws at–

Pixels drawn vs native–

Pixels saved–

The scene is drawn small, then stretched to the preview (a lower-resolution screen starts coarser). Zoom in on the thin lines and the text. Real upscalers like DLSS and FSR do far better than this simple stretch.