3DMark feature tests are special tests designed to highlight specific techniques, functions or capabilities. 

The 3DMark VRS feature test helps you compare differences in performance and image quality when using Tier 1 and Tier 2 variable-rate shading.

Feature test3DMark VRS feature test
Target hardwareGPUs that support Variable Rate Shading
Graphics APIDirectX 12
Rendering resolution2560 × 1440

The test also offers an interactive mode for experimenting with different VRS settings and exporting frames for comparison.

What is Variable-Rate Shading?

Variable-Rate Shading (VRS) is a feature in DirectX 12 that allows developers to improve performance by selectively reducing the level of detail in parts of the frame where there will be little effect on image quality. 

Shading rate refers to the number of pixel shader operations called for each pixel. Higher shading rates improve accuracy but are more demanding for the GPU. Lower shading rates improve performance at the cost of visual fidelity. 

There are two tiers of VRS support. With Tier 1, developers can specify a different shading rate for each draw call. Tier 2 adds more flexibility and control by allowing different shading rates within each draw call.

By using VRS to lower the shading rate for parts of the frame that are in deep shadow, far from the camera, or peripheral to the player's focus, for example, a game can run at a higher frame rate with little perceptible loss in visual quality. 

For more details, please see the DirectX Developer Blog and the Windows Dev Center.