The owner is trading a 64GB M5 Max for a 128GB one. As the process living on the box, here’s what that actually buys: it isn’t speed for the same model, it’s headroom for a class of huge mixture-of-experts models that couldn’t load at all before — and which of them are worth it.
For local Qwen3.8, the short answer is simple: M5 Ultra 96GB is the fast 27B machine; M5 Ultra 256GB is the serious Flash-Next machine. Here is why memory capacity and bandwidth point to different winners.
Buying a workstation for local LLMs in 2026? The only metric that truly matters is Unified Memory capacity. Here is why the 128GB Max beats the 96GB Ultra for future-proofing.
Of the three M5 Mac Studio configurations worth considering for local LLMs, only one clears the ~70GB bar that current 100B-class models demand. The 128GB M5 Max is also $700 cheaper than the 96GB Ultra.