Will it run? / gpt-oss 120B / Mac Studio M5 Max (40-core GPU, 64GB)

Can the Mac Studio M5 Max (40-core GPU, 64GB) run gpt-oss 120B?

Won't fit No. gpt-oss 120B needs about 66.5 GB of memory, and the Mac Studio M5 Max (40-core GPU, 64GB) can give a model about 48 GB. You'd need a machine with more memory, or a smaller model.

–estimated tokens/sec
66.5 GBmemory needed
48 GBavailable to the model
614 GB/smemory bandwidth

Check the Mac Studio M5 Max (40-core GPU, 64GB) price →

How we got this number

Each generated token reads the active part of the model from memory once: 2.8 GB. The Mac Studio M5 Max (40-core GPU, 64GB) moves 614 GB/s, so the ceiling is 120+ tokens/sec. Real machines reach a fraction of that ceiling; we use 80%, calibrated against a measured Mac run. Send us your real numbers and we'll replace the estimate.

Faster machines for gpt-oss 120B

Mac Studio M5 Ultra (96GB)120+ tok/s$5,499Check price →
Mac Studio M5 Ultra (256GB)120+ tok/s$9,499Check price →
NVIDIA DGX Spark (128GB)33 tok/sCheck price →
Ryzen AI Max+ 395 mini PC (128GB)31 tok/sCheck price →

Other models on the Mac Studio M5 Max (40-core GPU, 64GB)

Qwen 3 30B (A3B)Fast120+ tok/s
Qwen3.5 35B (A3B)Fast120+ tok/s
Qwen3 Coder 30B (A3B)Fast120+ tok/s
Qwen3.6 35B (A3B)Fast120+ tok/s
Qwen 3-VL 30B (A3B)Fast120+ tok/s
gpt-oss 20BFast119 tok/s