What Can You Run on a Mac Studio M3 Ultra? OpenClaw Cost Savings Guide
A practical guide mapping which AI models fit on the Mac Studio M3 Ultra (192GB unified memory, 819 GB/s bandwidth), real performance benchmarks, and how to use it with OpenClaw to slash API costs by running models locally.
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Introduction
The Mac Studio M3 Ultra with 192GB of unified memory sits in a sweet spot for local AI inference. It's not cheap at $6,000+ for the 192GB configuration, but it might pay for itself if you're burning through API costs with OpenClaw or other AI agents.
Here's the brutal truth: Running an AI agent can cost $200-700+ per month in API fees, especially if you're using Claude Opus for main sessions and Sonnet for sub-agents. But what if you could cut that by 50-90% by running the right models locally?
🎯 Bottom Line Up Front
The Mac Studio M3 Ultra can run 70B models at 30+ tokens/second, multiple 8B-30B models simultaneously, and handle all your embeddings, TTS, and image analysis locally. For heavy OpenClaw users, this could save $3,000-8,000 per year in API costs.
This guide maps exactly which models fit, real-world performance numbers from the community, and how to configure OpenClaw to route the right tasks to local models while keeping complex reasoning on cloud APIs.
What Models Fit in 192GB Unified Memory
Let's start with the math. The Mac Studio M3 Ultra comes with up to 192GB of unified memory shared between CPU and GPU. Here's what actually fits:
| Model | Full Precision (FP16) | 8-bit (Q8) | 4-bit (Q4) | Fits in 192GB? |
|---|---|---|---|---|
| Llama 3.1 8B | ~16 GB | ~8 GB | ~4 GB | ✅ Easily |
| Llama 3.3 70B | ~140 GB | ~70 GB | ~35 GB | ✅ Comfortably |
| Llama 3.1 405B | ~810 GB | ~405 GB | ~200+ GB | ❌ Too big |
| Qwen 2.5 32B | ~64 GB | ~32 GB | ~16 GB | ✅ Easily |
| DeepSeek V3 67B | ~134 GB | ~67 GB | ~33 GB | ✅ Comfortably |
| DeepSeek R1 14B | ~28 GB | ~14 GB | ~7 GB | ✅ Easily |
| Mistral 7B | ~14 GB | ~7 GB | ~3.5 GB | ✅ Easily |
| CodeLlama 34B | ~68 GB | ~34 GB | ~17 GB | ✅ Comfortably |
| Command R+ 104B | ~208 GB | ~104 GB | ~52 GB | ⚠️ Q4 only |
| Gemma 2 27B | ~54 GB | ~27 GB | ~13 GB | ✅ Easily |
⚠️ Important Memory Notes
- Context matters: These sizes assume ~8K context. Longer contexts need more memory.
- System overhead: macOS uses ~8-12GB, leaving ~180GB for models.
- Multiple models: You can run multiple smaller models simultaneously (e.g., 70B + 8B + embeddings).
- 405B models: Even Q4 quantized 405B models need 200-230GB — they won't fit comfortably.
Real Performance Benchmarks
Community benchmarks from r/LocalLLaMA, Hacker News, and YouTube show impressive performance on the M3 Ultra:
MLX Performance (Optimized)
Ollama Performance
LM Studio (MLX Backend)
vs Cloud API Response Times
🏆 Performance Winner: MLX
MLX (Apple's ML framework) consistently outperforms llama.cpp and Ollama by 20-30% on Mac hardware. LM Studio uses MLX as its backend and provides the best user experience for model management.
Runtime Comparison
Based on community benchmarks, here's how different runtimes perform on Mac Studio M3 Ultra:
- MLX direct: Fastest (230+ tok/s for small models, 33 tok/s for 70B)
- LM Studio (MLX): Nearly as fast, better UX (237 tok/s small, 33 tok/s 70B)
- Ollama: 20-30% slower but easiest API integration (149 tok/s small, 24 tok/s 70B)
- llama.cpp: Similar to Ollama, more manual setup required
OpenClaw Cost Mapping: The Big Picture
Here's where it gets interesting. Let's map OpenClaw's typical API usage to local alternatives and see the potential savings:
💸 Current API Costs (Monthly)
- Main agent (Opus)$150-400
- Sub-agents (Sonnet)$100-300
- Embeddings$50-150
- TTS/Whisper$30-80
- Vision/Image analysis$20-50
- Total$350-980
💚 Local + Hybrid Costs (Monthly)
- Main agent (Opus API)$150-400
- Sub-agents (Local 70B)$0
- Embeddings (Local)$0
- TTS/Whisper (Local)$0
- Vision (Local LLaVA)$0
- Electricity (~500W)$15-25
- Total$165-425
💰 Potential Savings: $185-555/month (53-67% reduction)
Over a year, that's $2,220-6,660 in savings. The Mac Studio M3 Ultra pays for itself in 12-18 months if you're a heavy API user.
What to Keep on API vs Run Locally
Keep on API (For Now)
- Main agent complex reasoning: Opus still outperforms all local models for complex multi-step reasoning
- Coding tasks requiring deep context: GPT-4 and Claude maintain quality edge
- Critical business decisions: When accuracy matters more than cost
Move to Local
- Sub-agent tasks: Research, writing, summarization — 70B models handle these well
- Embeddings: Local models like nomic-embed match OpenAI quality
- Audio transcription/TTS: Whisper and local TTS models are nearly identical to APIs
- Image analysis: LLaVA can handle most vision tasks
- Code completion: CodeLlama matches GitHub Copilot for many tasks
OpenClaw Model Routing Configuration
Here's how to configure OpenClaw to intelligently route tasks between local and cloud models:
1. Set Up Ollama on Mac Studio
# Install Ollama
curl -fsSL https://ollama.com/install.sh | sh
# Pull recommended models
ollama pull llama3.1:70b-instruct-q4_K_M # Sub-agent tasks
ollama pull nomic-embed-text # Embeddings
ollama pull llava:13b # Vision tasks
ollama pull codellama:34b-instruct-q4_K_M # Code assistance
2. Configure OpenClaw Model Routing
# ~/.openclaw/config/default.json5
{
"agents": {
"defaults": {
"model": {
"primary": "anthropic/claude-opus-4-6", // Main agent stays on Opus
"fallback": [
"ollama/llama3.1:70b-instruct-q4_K_M", // Fallback to local 70B
"anthropic/claude-sonnet-4-20250514" // Final fallback to Sonnet API
]
}
},
"subagents": {
"model": {
"primary": "ollama/llama3.1:70b-instruct-q4_K_M", // Sub-agents use local
"fallback": ["anthropic/claude-sonnet-4-20250514"] // API backup
}
}
},
"embeddings": {
"provider": "ollama",
"model": "nomic-embed-text"
},
"tts": {
"provider": "local", // Use local TTS
"whisper": {
"model": "large-v3",
"local": true
}
}
}
3. Network Setup (If Mac Studio is Remote)
If your Mac Studio is on a different machine from your OpenClaw gateway:
# On Mac Studio - expose Ollama API
export OLLAMA_HOST=0.0.0.0:11434
ollama serve
# In OpenClaw config
{
"providers": {
"ollama": {
"baseURL": "http://your-mac-studio-ip:11434/api"
}
}
}
4. Smart Task Routing Rules
Configure OpenClaw to route different task types automatically:
{
"taskRouting": {
"research": "ollama/llama3.1:70b-instruct-q4_K_M",
"writing": "ollama/llama3.1:70b-instruct-q4_K_M",
"coding-simple": "ollama/codellama:34b-instruct-q4_K_M",
"coding-complex": "anthropic/claude-sonnet-4-20250514",
"reasoning": "anthropic/claude-opus-4-6",
"vision": "ollama/llava:13b",
"embeddings": "ollama/nomic-embed-text"
}
}
Practical Considerations
Memory Management
- Ollama auto-unloads models after 5 minutes of inactivity to free memory
- Loading time: 70B models take 15-30 seconds to load initially
- Keep frequently used models loaded: Set longer timeout or use multiple smaller models
- Monitor memory usage: Use Activity Monitor to track model memory consumption
Performance Optimization
- Use Q4_K_M quantization for best quality/performance balance
- MLX > Ollama for pure speed but Ollama has better API compatibility
- Keep context reasonable: 8K-16K context is the sweet spot
- SSD matters: Fast storage helps with model loading
Latency Analysis
API Latency
Local Latency
Quality Trade-offs
⚠️ Be Realistic About Quality
Local 70B models are very good but not quite at Claude Opus level for complex reasoning. They excel at:
- Research and summarization
- Writing and editing
- Code completion and simple debugging
- Translation and content generation
Keep using Opus/Sonnet APIs for mission-critical reasoning, complex multi-step problem solving, and high-stakes decisions.
Clear Recommendations
🎯 The Opinionated Take
Based on real-world usage and community benchmarks, here's what you should actually do:
For Heavy OpenClaw Users ($300+/month in APIs)
- Buy the Mac Studio M3 Ultra with 192GB — it'll pay for itself in 12-18 months
- Run Ollama with Llama 3.1 70B Q4 for sub-agents and research tasks
- Keep main agent on Claude Opus for complex reasoning
- Move all embeddings and audio to local — immediate 100% savings on those APIs
- Use local vision models for non-critical image analysis
For Moderate Users ($100-300/month in APIs)
- Consider the Mac Studio M2 Ultra or wait for used M3 units
- Start with embeddings and TTS local — easiest wins
- Test local 70B for sub-agents — quality is surprisingly good
- Keep complex tasks on API until you're comfortable with local quality
For Light Users ($50-100/month in APIs)
- Stick with APIs for now — hardware cost doesn't justify savings
- Consider a Mac Mini M4 Pro for embeddings and simple tasks
- Focus on better prompt engineering to reduce token usage
Specific Model Recommendations
Best Models for Each Task
- Sub-agent reasoning: Llama 3.3 70B or DeepSeek V3 67B (Q4)
- Code assistance: CodeLlama 34B or DeepSeek Coder 33B (Q4)
- Embeddings: nomic-embed-text (beats OpenAI text-embedding-3-small)
- Vision tasks: LLaVA 13B or Qwen3-VL (good enough for most tasks)
- Fast responses: Qwen 2.5 14B or Llama 3.1 8B for simple questions
Runtime Recommendation
Use Ollama for OpenClaw integration. While MLX is faster, Ollama's API compatibility and model management make it the practical choice for production agent workflows.
Getting Started: Implementation Steps
Week 1: Test the Waters
- Install Ollama on your existing hardware
- Pull a smaller model:
ollama pull llama3.1:8b - Test quality against your typical sub-agent tasks
- Measure current API costs with
openclaw usage
Week 2-3: Scale Up Testing
- Try larger models on available hardware:
ollama pull llama3.1:70b-instruct-q4_K_M - Configure partial local routing for non-critical tasks
- Monitor quality vs speed trade-offs
- Test embeddings locally:
ollama pull nomic-embed-text
Week 4: Make the Call
- Calculate actual savings from your testing period
- If savings > $200/month: Order Mac Studio M3 Ultra 192GB
- If savings < $100/month: Stick with APIs and optimize prompts
- In between? Consider Mac Mini M4 Pro or wait for M4 Ultra
Production Deployment
# Full production setup script
#!/bin/bash
# Install Ollama
curl -fsSL https://ollama.com/install.sh | sh
# Pull production models
ollama pull llama3.1:70b-instruct-q4_K_M # Main local model
ollama pull nomic-embed-text # Embeddings
ollama pull llava:13b # Vision
ollama pull qwen2.5:14b-instruct-q4_K_M # Fast responses
# Configure OpenClaw
openclaw config set agents.subagents.model.primary "ollama/llama3.1:70b-instruct-q4_K_M"
openclaw config set embeddings.provider "ollama"
openclaw config set embeddings.model "nomic-embed-text"
# Test the setup
ollama run llama3.1:70b-instruct-q4_K_M "Test message"
echo "Setup complete!"
References
- r/LocalLLaMA: M3 Ultra Mac Studio Benchmarks
- r/LocalLLaMA: Quick-and-dirty test of 5 models on Mac Studio M3 Ultra 512 GB
- r/LocalLLaMA: A weekend with Apple's Mac Studio with M3 Ultra
- Performance of llama.cpp on Apple Silicon M-series
- Llama 3 Guide: Every Size from 1B to 405B
- Ollama VRAM Requirements: Complete 2026 Guide
- A Comparative Study of MLX, MLC-LLM, Ollama, llama.cpp
- Local LLM Speed Test: Ollama vs LM Studio vs llama.cpp
- Speed Test #2: Llama.CPP vs MLX with Llama-3.3-70B
- The Real Cost of Running an AI Agent: OpenClaw Cost Optimization Guide
- Mac Studio M3 Ultra vs DIY GPU Rig for Local AI Inference
- OpenClaw Model Routing Guide: Which AI Model for Which Task
- 13 Best Embedding Models in 2026: OpenAI vs Voyage AI vs Ollama
- Best Ollama Embedding Models: A Guide for RAG Applications
- OpenAI Audio Model Pricing Discussion