Variable Rate Shading feature and performance impact

As you might not be aware, Nvidia has added support for Variable Rate Shading feature in their Turing GPUs, and Intel did the same. If you do not know what it is, here is a nice article:
https://developer.nvidia.com/vrworks/graphics/variablerateshading

Basically it allows to boost performance by decreasing the processing of parts of the frame which are less visible to a person. Now 3DMark has added the test for it in their benchmark. Here are the results if you cannot test it yourself:
https://hothardware.com/news/3dmark-variable-rate-shading-test-performance-gains-gpus
As you can see, the performance difference is very large. Unfortunately current AMD hardware has no support for it so if you are fan of AMD - you must wait for next GPU generation from them. Fortunately there are no games right now which use this feature, but hopefully more will use it since the performance increase is very big.

 

Actually Wolfenstein II: The New Colossus does, and the performance boost isn’t that big, something like 10-15% on the most aggressive VRS setting if I’m remembering correctly. Foveated rendering is quite common in VR as well, and the older Shadow Warrior 2 supported multi-res shading, the precursor to VRS. As per usual, synthetic benchmarks will fluff up a new feature more than real-world apps do.

 

True, the benchmark always use the best case of new technology so performance difference is usually exaggerated but doesn't mean it can't be achieved in some scenes in actual games ;-)

 

Using the Interactive mode is interesting. I was seeing ~30% or more frame rate increase depending on shading settings. There is a discernible visual quality difference in captured frames when you really look. But I can imagine in most games where you're running around it will not be noticed.