What sort of AMD gains that would give them such huge much gains? No one announced anything, not the developer or AMD, nor any other test site for that matter. I don't think something big like that would go announced by any of the interested parties.
I did some investigation, and here are the results:
In
TPU testing the 4090 is 7x times faster than 6900XT at 1440p.
In
Tomshardware testing the 4090 is 7.5x times faster than 6900XT at 1440p.
It's also ~7x times faster using
ComputerBase testing.
However, in the original
GameGPU benchmark (version 2.0 of the game), the 4090 is only 5x times faster than 6900XT at 1440p.
So something wrong with the test sequence GameGPU is using, causing it to give results with reduced gaps between AMD and NVIDIA GPUs.
As for your other point, the 4090 is only 4x faster than 6900XT in Quake 2 RTX and Minecraft RTX.
Test de la nouvelle carte graphique GeForce RTX 4090 au travers du modèle Founders Edition de Nvidia. Au programme, 26 jeux testés, dont 20 en rastérisation et 15 en Ray Tracing, 13 benchmarks, des mesures de consommation, nuisances sonores, températures et imagerie infrarouge.
www.comptoir-hardware.com
In Portal RTX, it's 18x times faster at any resolution.
Valve has teamed up with NVIDIA to remaster their smash-hit Portal with ray tracing. Unlike most other titles out there, which combine rasterization and ray tracing, Portal with RTX is fully path traced, which enables astonishing realism, but also comes with a huge performance hit.
www.techpowerup.com