Everything works, but the delay increases
FSR 3 technology, as you know, is available not only for AMD video cards. For Nvidia adapters, AMD itself talks about supporting at least models of the GeForce RTX 20 generation. However, technically, no one is stopping you from launching the technology on older cards. And this was done by blogger Daniel Owens. He tested the GeForce GTX 1060 and GTX 1070 in the game Immortals of Aveum.
AMD is doing for older GeForce video cards what Nvidia itself did not do.
It turned out that not only FSR 3 itself works with these cards, but also the frame generation technology. For example, for the GTX 1060 in the native rendering resolution (that is, with FSR Nativ AA) and the frame generator enabled, performance increased from 20-22 fps to 32-34 fps, that is, about one and a half times. However, the problem is that the delay also increased significantly: up to 200 ms. Because of this, playing is no longer so comfortable.
The same performance increase, but without a strong increase in latency, is provided by FSR in Quality mode and without a frame generator, but here the upscale still affects image quality.
The situation was the same with the GTX 1070, only adjusted for the greater performance of the adapter itself. Thus, FSR 3 makes it possible to use older GeForce video cards in a way that without AMD technology they would not have been able to handle or would have done much worse.