Looking at the prices, The 4090 is about 3/4 of the price of a base model M2 Ultra Mac Studio, which has 64GB RAM. With the rest of the PC to go with the graph

Looking at the prices, The 4090 is about 3/4 of the price of a base model M2 Ultra Mac Studio, which has 64GB RAM. With the rest of the PC to go with the graphics card, it's about 7/8s of the price of an Ultra. Then you have the compatibility. Do you want your software to be CUDA compatible or Metal compatible? If you're writing the software, maybe you want both! The budget option is to go with a used 3090, which still has greater memory bandwidth than the M2 Ultra. In terms of FP16 Flops on the GPU, you have: M2 Ultra, 27 TFLOPS RTX 3090, 35 TFLOPS RTX 4090, 82 TFLOPS https://www.cpu-monkey.com/en/igpu-apple_m2_ultra_76_core https://www.cpu-monkey.com/en/igpu-apple_m2_ultra_76_core https://www.techpowerup.com/gpu-specs/geforce-rtx-3090.c3622 https://www.techpowerup.com/gpu-specs/geforce-rtx-3090.c3622 https://www.techpowerup.com/gpu-specs/geforce-rtx-4090.c3889 https://www.techpowerup.com/gpu-specs/geforce-rtx-4090.c3889