Each 3DMark benchmark is rendered at a fixed resolution regardless of hardware. This is the rendering resolution. The rendered frames are then scaled to fit your system's Windows desktop resolution. This scaling has a negligible effect on the benchmark in most cases, and scores are comparable regardless of the desktop resolution you use.
Benchmark rendering resolution and Windows desktop display resolution are independent. You don't need to have a 4K monitor to run a 4K benchmark like Time Spy Extreme or Fire Strike Ultra. The benchmark will render at 4K then scale the frames to your PC's desktop display resolution.
Impact on CPU-limited systems
When a benchmark is limited by the CPU, or when the frame rate is very high, image scaling may have a small impact on the benchmark score. Both scenarios can be avoided, however, by choosing the right benchmark for your system.
Impact of 4K and other ultra-high resolutions
If you have a 4K desktop resolution but your GPU is not very powerful, the image scaling may require a considerable amount of GPU resources and video memory. Running with integrated graphics or a low-end discrete GPU at 4K desktop resolution or higher is not recommended. Your score may be degraded by the performance penalty of image scaling.
As a workaround, you can override the output resolution with the Scaled Resolution setting on the Options screen. For most benchmarks, choosing 1920 × 1080 (1080p) for the output resolution will be fine.
The Scaling Mode setting on the Options screen lets you choose between Centered and Stretched Scaling.
Centered scaling preserves the original aspect ratio. It adds a letterbox effect if your desktop resolution does not have a 16:9 aspect ratio.
Stretched scaling will stretch the image to fill the display without preserving the original aspect ratio. You could use stretched scaling to fill a triple-monitor setup, for example. Stretched scaling does not change the workload. The benchmark still renders to the internal rendering resolution, it is just scaled differently to your display.
How to change a benchmark's rendering resolution
In 3DMark Advanced Edition and 3DMark Professional Edition, you can use custom benchmark settings to change the internal rendering resolution. Please remember that custom runs do not produce an overall score and the sub-scores cannot be compared with scores obtained with default settings.
How to change a benchmark's scaled resolution
You can use the Scaled Resolution setting on the Options screen to set the scaling resolution to something other than your current desktop display resolution. This option does not affect your score.
Optimal settings for overclockers
If you're aiming for the highest possible score in a benchmark—for an overclocking contest, for example—matching your desktop resolution to the benchmark's internal rendering resolution may provide a very slight performance gain.