48GB is maybe just enough to squeeze a quantized 70B model in, like Llama 3.3, but you'll need to raise the GPU memory allocation limit [1] and it might not be super fast.
You could also try Qwen 2.5 32b, which you should just work with ollama or LM Studio with no config changes.
I've got a 32gb M1 Max and a 24gb 4090, and I barely ever run models on my Mac, as the memory bandwidth and compute for prefill is much better on the 4090. But I'm essentially locked out of Llama 3 70B class models, which I only use via API.
