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Guides · Hardware · 6 min read

Mac or Nvidia for local AI? The honest comparison

Two camps dominate local AI at home: people with an Nvidia card in a PC, and people with an Apple Silicon Mac. Each side has a real advantage, and which one matters depends on what you want to run.

Capacity: Mac wins

Apple Silicon uses unified memory shared by CPU and GPU. A Mac Studio with 128 GB can load a 70B model at Q8 or a 120B mixture-of-experts model, something no consumer Nvidia card can do. Even a 32 GB MacBook Pro comfortably runs 27B to 32B models that would need a 24 GB RTX 4090. If you want the biggest, smartest models, a Mac with a lot of memory is the cheapest path.

Speed: Nvidia wins

Generation speed is governed by memory bandwidth. An RTX 4090 reads memory at about 1,000 GB/s and a 5090 at nearly 1,800. A base M4 manages around 120 GB/s, an M4 Pro 273, an M4 Max 546. For an 8B model that is the difference between 100 tokens per second on a 4090 and 25 on an M4 Max. Nvidia also has the broadest software support: every new inference trick ships for CUDA first.

Price and practicality

A used RTX 3090 with 24 GB costs a fraction of a Mac Studio and runs 32B models fast, but you need a desktop with a big power supply. A Mac runs quietly on a desk and doubles as a normal computer. Laptops are a special case: Nvidia laptop cards top out at 16 GB and throttle under load, so for a portable local AI machine a MacBook Pro with 36 GB or more is hard to beat.

Rough guide

You wantPick
Fastest chat with 8B to 14B modelsAny Nvidia card with 12 GB or more
Run 32B models wellRTX 3090 / 4090 / 5090, or Mac with 48 GB+
Run 70B and largerMac Studio 96 GB+, or two 24 GB cards
A laptop that does it allMacBook Pro M4 Max, 48 GB or more
Cheapest entryUsed RTX 3060 12 GB

Put your actual machine into the checker to see the specific list for your memory and bandwidth.

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