The RTX speed up is scene dependent, so while 2019 havana scene, octane 1,2 and 3 splash screen scenes get 2-4x speed boost, that is not the case with the the simpler octane bench scenes like idea which is a light bulb in a room, and all shading, little tracing we can push to RT.
For now, turning on RTX, getting a 20% OB boost with the existing OB4 scenes actually makes sense because it is a good measure of what almost any scene is likely to do on RTX - after all the OB4 scenes render identically with RTX on, and served as our benchmark for 5 years before RTX was a factor.
That said, the RTX on boost on Ampere for these scenes may not be the same as Turing, making classic OB potentially higher with RTX on on Ampere. We’ll have to wait until that is all public.
Beyond standard OB, we have done deep testing 40+ heavy real world scenes both on ampere, turing et al. with RTX on and off, so we now have a very good sense of the real world averages relative to classic OB. We are planning to have a future OctaneBench add more if these heavier scenes, which will likely push OB higher on Ampere/Turing relative to the 100 OB set on a 980.
We’ll share these preliminary results as well once the cards are public. But, rest assured, the official OB scores you will see for Ampere are really impressive relative to last gen, either with RTX on or off,
classic OB scenes or with new OB candidate scenes.