What is the biggest model the L40S can run?

Llama 3.3 70B, which needs about 45 GB, on the 48 GB version at about 11 tok/s.

What is the biggest model the Apple M3 Ultra can run?

Qwen3 235B-A22B, which needs about 144 GB, on the 512 GB version at about 22 tok/s.

L40S vs Apple M3 Ultra for local AI

The Apple M3 Ultra fits more: up to Qwen3 235B-A22B, against Llama 3.3 70B on the L40S. The L40S generates about 5% faster on any model both can run, because it has 864 GB/s of memory bandwidth to the Apple M3 Ultra's 819 GB/s.

The numbers that matter

Memory and bandwidth

Memory decides which models fit. Bandwidth decides how fast they generate, because every token reads the model's active weights once.

	L40S	Apple M3 Ultra
Memory	48 GB VRAM	96 or 256 or 512 GB unified memory
Usable for models	All 48 GB	About 384 GB of 512 GB
Bandwidth	864 GB/s	819 GB/s
Biggest model that fits	Llama 3.3 70B	Qwen3 235B-A22B
Best everyday pick	Qwen3 32B, ~24 tok/s	Qwen3 235B-A22B, ~22 tok/s

Model by model

Every model, side by side

Estimated generation speed at the largest memory size each was sold in (48 GB and 512 GB).

Model	L40S	Apple M3 Ultra
Qwen3 4B About 4 GB	~190 tok/s Runs great	~180 tok/s Runs great
Qwen3 8B About 7 GB	~91 tok/s Runs great	~87 tok/s Runs great
Gemma 3 12B About 10 GB	~59 tok/s Runs great	~56 tok/s Runs great
Qwen3 14B About 11 GB	~51 tok/s Runs great	~48 tok/s Runs great
gpt-oss 20B About 16 GB	~150 tok/s Runs great	~140 tok/s Runs great
Gemma 3 27B About 19 GB	~28 tok/s Usable	~26 tok/s Usable
Qwen3 30B-A3B About 21 GB	~150 tok/s Runs great	~140 tok/s Runs great
Qwen3 32B About 22 GB	~24 tok/s Usable	~23 tok/s Usable
Llama 3.3 70B About 45 GB	~11 tok/s Usable	~10 tok/s Usable
gpt-oss 120B About 67 GB	Needs 67 GB	~99 tok/s Runs great
Qwen3 235B-A22B About 144 GB	Needs 144 GB	~22 tok/s Usable
DeepSeek R1 671B About 406 GB	Needs 406 GB	Needs 406 GB

Which should you get?

It depends. The Apple M3 Ultra fits bigger models; the L40S runs the models both fit faster. Price matters as much as either number: check used prices on the builds page, where every parts list has a measured or estimated speed.

How we estimate

Both columns use the same formula: memory bandwidth divided by the weights read per token, calibrated on our own rack, with Ollama's default 4-bit sizes. Real results are usually within about a third. Measured either one? Send us the number.

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