You're not wrong that the RTX 4090 will be much more powerful than an M2 Ultra, but you don't have any idea what you're talking about when you're comparing spec

You're not wrong that the RTX 4090 will be much more powerful than an M2 Ultra, but you don't have any idea what you're talking about when you're comparing specs. You might be able to compare the number of CUDA cores to the ALU count of the Apple GPUs. I don't know what that is for M2 Ultra yet, but for the 64 core M1 Ultra each core had 16 execution units and each of those had 8 ALUs, for a total of 8,192 ALUs. The M1 Ultra's FP32 performance was in the ballpark of 21tflops - assuming a ~30% improvement in the M2 Ultra that takes us to ~27tflops. Google suggests that for the RTX 4090 it's 83tflops.