Q: How fast is gpt-oss 20B MoE on the Apple M3 Max?

~100–150 tok/s (active-expert estimate) on the Apple M3 Max. computed roofline: 400 GB/s × 0.55–0.80 efficiency window / 2.1GB (Q4_K_M) — bands, never points. MoE: file is 14GB (that decides fit) but only ~3B of experts activate per token (~2.1GB streamed) — band below is the active-expert estimate, optimistic; community MoE rows run several× the naive bandwidth math

Question 1

Can the Apple M3 Max run gpt-oss 20B MoE?

Accepted Answer

gpt-oss 20B MoE needs about 14.19GB working set (weights 14GB + KV cache 0.19GB at 4k context). The Apple M3 Max offers ~34GB usable — verdict: full. 14.2 GB needed of 34 GB usable — headroom for context

Question 2

How fast is gpt-oss 20B MoE on the Apple M3 Max?

Accepted Answer

~100–150 tok/s (active-expert estimate)

computed roofline: 400 GB/s × 0.55–0.80 efficiency window / 2.1GB (Q4_K_M) — bands, never points.

MoE: file is 14GB (that decides fit) but only ~3B of experts activate per token (~2.1GB streamed) — band below is the active-expert estimate, optimistic; community MoE rows run several× the naive bandwidth math

Question 3

What should I run gpt-oss 20B MoE on instead?

Accepted Answer

Tesla P40 (24GB, used) runs it fully ($290).

Can the Apple M3 Max run gpt-oss 20B MoE?

Run gpt-oss 20B MoE on instead