How much memory does Llama 3.1 8B Instruct need at Q4?

The Q4 figure used here is 4.9 GB. GGUF file size from the linked Hub repo. KV cache was not added, because this model's attention shape is not in the catalog.

What is the cheapest catalog device that runs Llama 3.1 8B Instruct at Q4?

GeForce RTX 5050, list price $249.

How fast is Llama 3.1 8B Instruct on the Mac Studio M3 Ultra 96GB, as a bandwidth estimate?

About 51.0 tok/s at FP16. That is device bandwidth divided by active weight bytes, not a measured run.

Yes. Llama 3.1 8B Instruct fits on the Mac Studio M3 Ultra 96GB at FP16, with 47.9 GB of headroom. Usable memory is 67.2 GB.

Can the Mac Studio M3 Ultra 96GB run Llama 3.1 8B Instruct?

Data updated 16 October 2026. Last reviewed the same day, when this catalog snapshot was written.

Usable memory on this 96 GB unified-memory config is 67.2 GB (70% of the sticker figure). A result under 2 GB of headroom is labeled tight.

Quant ladder

Estimated memory for Llama 3.1 8B Instruct on Mac Studio M3 Ultra 96GB
Quant	Estimate	Headroom	Est. tok/s	Verdict
Q4	4.9 GB	62.3 GB	166 tok/s	Yes
Q8	9.6 GB	57.6 GB	102 tok/s	Yes
FP16	19.3 GB	47.9 GB	51.0 tok/s	Yes

GGUF file size from the linked Hub repo. KV cache was not added, because this model's attention shape is not in the catalog.
Formula estimate: parameter count × bytes per weight × 1.20. No GGUF file size is stored for this quant.
Tokens/sec is a bandwidth roofline: GB/s divided by active weight GB. It is not a measured generation speed.

KV cache at 8K and 32K

No KV-cache estimate. The public config for this model was gated, missing, or not a GQA or MLA shape this catalog knows how to read.

Offload

This machine has one memory pool. Weights are not offloaded to a second bank of system RAM.

Ollama

This command pulls the Q4_K_M file from unsloth/Llama-3.1-8B-Instruct-GGUF, the Hub repo whose file size is used above. It is not an official Ollama library tag.

ollama run hf.co/unsloth/Llama-3.1-8B-Instruct-GGUF:Q4_K_M

Other picks

Cheapest catalog device at Q4: GeForce RTX 5050
Closest catalog model that still fits at Q4: Llama 4 Scout.

All hardware for Llama 3.1 8B Instruct · All models for the Mac Studio M3 Ultra 96GB

Questions

How much memory does Llama 3.1 8B Instruct need at Q4?: The Q4 figure used here is 4.9 GB. GGUF file size from the linked Hub repo. KV cache was not added, because this model's attention shape is not in the catalog.
Can the Mac Studio M3 Ultra 96GB run Llama 3.1 8B Instruct?: Yes. Llama 3.1 8B Instruct fits on the Mac Studio M3 Ultra 96GB at FP16, with 47.9 GB of headroom. Usable memory is 67.2 GB.
What is the cheapest catalog device that runs Llama 3.1 8B Instruct at Q4?: GeForce RTX 5050, list price $249.
How fast is Llama 3.1 8B Instruct on the Mac Studio M3 Ultra 96GB, as a bandwidth estimate?: About 51.0 tok/s at FP16. That is device bandwidth divided by active weight bytes, not a measured run.