Resolution scaling is a technique used in video games and rendering engines to render the game at a lower or higher resolution than your monitor's native display resolution, and then scale it to fit your screen. This allows you to trade visual clarity for better performance (FPS) or vice versa.
Downscaling (e.g., 75%): Renders the game at a lower resolution (fewer pixels), which significantly reduces the workload on your GPU, resulting in higher frame rates. The image is then stretched to fill your screen, which can make it look softer or blurrier.
Upscaling / Supersampling (e.g., 150%): Renders the game at a higher resolution (more pixels) than your display, then shrinks it down. This acts as a high-quality anti-aliasing method, making the image much sharper and clearer, but drastically reduces performance.
Spatial vs. Temporal Upscaling
Modern games often feature advanced upscaling technologies that perform better than traditional resolution scaling:
Basic Resolution Scaling: A simple, uniform scaling that can often look blurry when downscaled.
Temporal Upscaling (DLSS, FSR, XeSS): Uses data from previous frames (and sometimes AI) to reconstruct a high-resolution image from a lower-resolution render. This provides a massive performance boost while maintaining image quality that rivals or sometimes beats native resolution.
How does scaling affect performance?
Performance in games is heavily tied to the number of pixels your GPU has to draw every frame. Because resolution is two-dimensional (width and height), changing the render scale affects the total pixel count quadratically.
For example, a render scale of 50% doesn't mean you are rendering half the pixels. It means both the width and the height are halved, resulting in only 25% of the original pixels being rendered (0.5 * 0.5 = 0.25). This massive reduction in pixel count often leads to a substantial increase in frame rates.