Current model Desktop workstation · 2025

Mac Studio M3 Ultra (512GB)

M3 Ultra with 512GB unified memory and 819GB/s memory bandwidth; currently available new.

Check current configuration Technical data

RAM: 512 GB
Bandwidth: 819 GB/s
Comfortable model range: 405B

Local AI fit

405B is the realistic daily range

Capacity estimate: up to roughly 405B comfortably, 500B tightly. Context, quantization, and running apps change real-world fit.

Comfortable: 405B
Tight: 500B
Capacity edge: 500B

500B is a capacity edge, not a blanket promise: it generally requires strong weight quantization, a short context, and little parallel load. KV-cache precision and the model architecture can materially change the result.

512GB explained Why unified memory is more than model weights Understand quantization, KV cache, macOS headroom, and the difference between “fits” and “runs well.” Open RAM guide

Purchase status

Current model

Available new. Check the exact configuration and current price with the seller.

Generation: M3-Ultra
Released: 2025
Data checked: 2026-07-28

At a glance

Technical Specs

Desktop workstation

Chip: M3-Ultra
RAM: 512 GB
Memory bandwidth: 819 GB/s
Form factor: Desktop workstation
Release year: 2025

What works well

Pros

512GB unified memory
819GB/s memory bandwidth

What to consider

Cons

Actual token rates depend on model and runtime

Data verified

Product data and links last checked on 2026-07-28. Prices and availability can change at any time.

Apple technical source Technical data follows Apple specifications; not an independent performance guarantee.

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