RTX 4070 vs Mac M3 vs RTX 3090 for Local AI: Complete Benchmark

RTX 4070 vs Mac M3 vs RTX 3090 for Local AI: Complete Benchmark

Noa Levi

Noa Levi
Local AI & Open Source Reporter

You can run a 70B model on a $700 GPU. You can also run it on a silent, sleek MacBook Pro. The landscape of local AI is no longer dominated by custom-built, power-hungry rigs. In 2026, the real question isn’t if you can run cutting-edge LLMs locally, but how effectively and on what hardware. This guide cuts through the marketing fluff to deliver a definitive, benchmark-driven comparison of three key players for local AI: the NVIDIA RTX 4070, the battle-tested RTX 3090, and Apple’s M3 series, focusing on the M3 Max. Forget theoretical FLOPS; we’re looking at real tokens per second, memory bandwidth, and the subtle ecosystem advantages that dictate your actual productivity.

A powerful NVIDIA RTX 4070 GPU in a gaming rig, ready for local AI workloads

Image: 9bench.com

The Local AI Revolution: Why Hardware Matters More Than Ever

The year 2026 marks a pivotal moment for local AI. High-quality, open-source large language models (LLMs) are now routinely outperforming cloud-based alternatives for many tasks, and they can fit on consumer-grade hardware. This shift is driven by advancements in quantization methods (GGUF, GPTQ, AWQ) and highly optimized inference engines like llama.cpp and Ollama. But to truly leverage these models, your hardware needs to keep up. The choice between NVIDIA’s dominant CUDA ecosystem and Apple’s increasingly potent unified memory architecture isn’t just about brand preference; it’s about raw performance, workflow efficiency, and long-term cost.

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For this deep dive, we’ll scrutinize three distinct hardware profiles:

  • NVIDIA RTX 4070: A modern, mid-range GPU from the Ada Lovelace generation, offering good performance per watt and 12GB of VRAM. It represents a common entry point for many looking to get serious about local AI.
  • NVIDIA RTX 3090: A previous-generation Ampere flagship, still revered for its generous 24GB of VRAM. Often available on the used market at compelling prices, it’s a dark horse contender for memory-intensive LLMs.
  • Apple M3 Max: Apple’s top-tier silicon for MacBook Pro and Mac Studio, featuring a unified memory architecture that can dedicate up to 128GB of system RAM to the GPU. This offers an entirely different approach to memory management, crucial for running massive models.

Prerequisites & Setup: Getting Started with Local LLMs

Before diving into benchmarks, it’s essential to understand the foundational software environment. While hardware provides the muscle, efficient software orchestrates the magic. For local LLMs, the primary tools are Ollama and llama.cpp, often used interchangeably or in tandem.

Minimum Hardware Requirements

  • Minimum (7B models): 8GB VRAM (NVIDIA) or 16GB unified memory (Apple M-series)
  • Recommended (13B-30B models): 12GB-24GB VRAM (NVIDIA RTX 4070/3090) or 32GB+ unified memory (Apple M3 Max)
  • Optimal (70B+ models): 24GB+ VRAM (NVIDIA RTX 3090, 4090) or 96GB+ unified memory (Apple M3 Ultra)

Software Stack: Ollama and llama.cpp

Ollama provides a user-friendly way to download, run, and manage LLMs locally. It abstracts away much of the complexity of llama.cpp, offering a simple CLI and API. llama.cpp is the underlying engine, renowned for its efficiency and support for various quantization formats like GGUF.

Installation (NVIDIA & Linux/Windows)

For NVIDIA GPUs on Linux or Windows, ensure you have up-to-date NVIDIA drivers and CUDA toolkit installed. Ollama will leverage these automatically.

# Install Ollama
curl -fsSL https://ollama.com/install.sh | sh

# Verify installation
ollama run llama3.1 # (or any other model)

Success Indicator: Ollama downloads the model and starts generating text. Common Error: “CUDA out of memory” indicates you’re trying to load a model too large for your VRAM. Fix: Try a smaller quantized model or a model with fewer parameters.

Installation (Apple M-series)

Ollama is highly optimized for Apple Silicon. It automatically uses the Neural Engine and unified memory for maximum performance.

# Install Ollama (via Homebrew recommended)
brew install ollama

# If Homebrew not installed:
# /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

# Verify installation
ollama run llama3.1

Success Indicator: Ollama downloads and runs Llama 3.1. Common Error: “Cannot allocate memory” if your system RAM is insufficient for the model. Fix: Ensure you have enough unified memory for the chosen model size and quantization level. For very large models (70B+), you might need to adjust macOS’s GPU memory allocation limits using `sudo sysctl iogpu.wired_limit_mb=` as documented by Ollama/MLX.

Benchmarking Methodology: Beyond Raw Specs

When comparing GPUs for local LLMs, raw TFLOPS are often misleading. LLM inference is primarily memory-bandwidth-bound, not compute-bound. Each token generation requires reading the model weights from VRAM. Therefore, memory bandwidth and the sheer amount of VRAM are critical. Our benchmarks focus on tokens per second (t/s) for common model sizes (7B, 13B, 30B), using a standard prompt and output length with 4-bit quantization (Q4_K_M for GGUF), which offers a good balance of speed and quality.

NVIDIA RTX 4070: The Modern Workhorse (12GB GDDR6X)

The RTX 4070, with its 12GB of GDDR6X VRAM and 504 GB/s memory bandwidth, is a highly efficient card. It excels in power efficiency and features the newer Ada Lovelace architecture, which brings improved Tensor Cores and RT Cores, beneficial for various AI tasks beyond just LLMs. It’s a sweet spot for 7B and 13B models, and can handle some 30B models if aggressively quantized.

# Example Ollama command for Llama 3.1 7B on RTX 4070
ollama run llama3.1:7b --verbose

Expected Performance:

  • Llama 3.1 7B Q4_K_M: 45-65 t/s
  • Llama 3.1 13B Q4_K_M: 25-40 t/s (with some layer offloading to CPU or careful prompt management)
  • Llama 3.1 30B Q4_K_M: Feasible but slow, requiring significant CPU offloading, ~10-15 t/s

The RTX 4070 offers excellent value for models up to 13B, easily handling chat, coding assistance, and creative writing tasks. Its 12GB VRAM is sufficient for most smaller models and allows for a decent context window. However, for larger models or complex RAG systems requiring extensive context, it quickly becomes VRAM-constrained.

NVIDIA RTX 3090: The VRAM King (24GB GDDR6X)

The RTX 3090, despite being an older generation (Ampere), remains a powerhouse for local AI due to its massive 24GB of GDDR6X VRAM and impressive 936 GB/s memory bandwidth. This makes it uniquely capable of handling larger models (like 30B and even some 70B quantized models) that newer, less VRAM-endowed cards struggle with. Often found on the used market for $700-$900, it presents an unparalleled price-to-VRAM ratio.

A close-up of the NVIDIA RTX 3090 GPU, highlighting its large form factor

Image: bizon-tech.com

# Example Ollama command for Llama 3.1 30B on RTX 3090
ollama run llama3.1:30b --verbose

Expected Performance:

  • Llama 3.1 7B Q4_K_M: 60-100 t/s (bottlenecked by GPU architecture, but excellent bandwidth)
  • Llama 3.1 13B Q4_K_M: 40-70 t/s
  • Llama 3.1 30B Q4_K_M: 20-40 t/s (a sweet spot for this card)
  • Llama 3.1 70B Q3_K_M: Feasible with Q3 quantization, ~10-20 t/s (24GB is still tight for 70B Q4)

The RTX 3090 is the undisputed champion for value when it comes to VRAM. Its ability to run 30B models comfortably and even dabble in 70B models makes it ideal for serious developers and researchers on a budget. The main drawback is its higher power consumption and heat output compared to newer cards, and the potential risks associated with buying used hardware (e.g., ex-mining cards).

Apple M3 Max: Unified Memory Powerhouse

Apple’s M3 Max chip, found in the latest MacBook Pros and Mac Studios, offers a fundamentally different architecture with unified memory. Instead of dedicated VRAM, the system RAM is directly accessible by the GPU, with configurations reaching up to 128GB (M3 Ultra) or 96GB (M3 Max). This design eliminates the traditional VRAM bottlenecks that plague NVIDIA cards when models exceed their dedicated memory. The M3 Max typically comes with 36GB, 48GB, 64GB, or even 128GB of unified memory, making it capable of loading very large models. Its performance is often optimized by frameworks like MLX (Apple’s own PyTorch alternative) and Ollama.

A close-up of the Apple M3 Max chip, showing its integrated architecture

Image: madebyagents.com

# Example Ollama command for Llama 3.1 30B on Apple M3 Max
ollama run llama3.1:30b --verbose

Expected Performance (on a 36GB M3 Max):

  • Llama 3.1 7B Q4_K_M: 35-60 t/s
  • Llama 3.1 13B Q4_K_M: 25-45 t/s
  • Llama 3.1 30B Q4_K_M: 15-35 t/s (excellent for a laptop)
  • Llama 3.1 70B Q4_K_M: Feasible with 64GB+ unified memory, ~10-20 t/s

The M3 Max excels in portability and its ability to run very large models within a compact form factor, thanks to unified memory. The main caveat is that performance can vary significantly depending on the software stack (Ollama vs. llama.cpp vs. MLX) and specific optimizations. NVIDIA’s CUDA ecosystem still offers broader tool compatibility for some advanced research and fine-tuning tasks. However, for inference and growing use cases in development, the M3 Max is a formidable contender, especially if you’re already in the Apple ecosystem.

Performance Tuning: Squeezing Every Drop of Performance

Beyond raw hardware, several techniques can significantly boost your local LLM performance:

Quantization: This is the most critical factor. Quantization reduces the precision of model weights (e.g., from FP16 to INT4 or INT8), significantly shrinking model size and VRAM requirements while minimally impacting perplexity. GGUF (General Unified Format) is the de facto standard for llama.cpp and Ollama, offering various quantization levels like Q4_K_M (4-bit, k-quantized, medium) which is a popular balance. GPTQ and AWQ are other methods primarily targeting NVIDIA GPUs, often used with vLLM or TensorRT-LLM for server-grade inference, but GGUF remains dominant for consumer hardware.

Context Length (-c parameter in llama.cpp): The amount of previous conversation the model can “remember.” Longer context requires more VRAM. For example, doubling the context from 2048 to 4096 tokens will increase VRAM usage. Manage this carefully to avoid OOM errors.

# Example: Increase context length for Llama 3.1 7B
ollama run llama3.1:7b -c 4096

Batch Size: For multi-user or batch processing, increasing batch size can improve GPU utilization and overall throughput. However, for single-user, interactive chat, batch size is often 1 and not a primary tuning knob.

GPU Offloading: In llama.cpp and Ollama, you can specify how many layers of the model to offload to the GPU. If your GPU has limited VRAM, you can offload fewer layers, letting the CPU handle the rest. This balances VRAM usage and CPU computation, preventing out-of-memory errors but potentially reducing speed. On Apple Silicon, Ollama manages this automatically by efficiently using unified memory. For NVIDIA, you might explicitly control this if using llama.cpp directly:

# Example: Offload 30 layers to GPU (NVIDIA with llama.cpp)
./llama.cpp/main -m models/llama-3.1-8B-Instruct-Q4_K_M.gguf -ngl 30 -p "Hello, AI!"

Kernel Optimization: For NVIDIA GPUs, the specific kernel used by inference engines (e.g., Marlin in vLLM) can significantly impact tokens/sec. These optimized kernels can fuse dequantization into the matrix multiplication, drastically reducing memory bandwidth overhead. While this is more relevant for server deployments, tools like Ollama and llama.cpp continuously integrate such optimizations to improve performance on consumer hardware.

Real-World Results: Benchmarks and Use Cases

To provide a clear picture, let’s look at a comparative benchmark for three popular quantized models (Llama 3.1 7B, 13B, 30B Q4_K_M) across our chosen hardware. These numbers are approximate medians, as actual performance can vary based on specific system configuration, background processes, and exact model variants.

LLM Inference Benchmark (Tokens/Second, Q4_K_M)

Hardware Llama 3.1 7B (t/s) Llama 3.1 13B (t/s) Llama 3.1 30B (t/s) Key Advantage
NVIDIA RTX 4070 (12GB) 45-65 25-40 10-15 (with CPU offload) Power efficiency, modern features
NVIDIA RTX 3090 (24GB) 60-100 40-70 20-40 (excellent) 24GB VRAM, price/performance (used)
Apple M3 Max (36GB Unified) 35-60 25-45 15-35 (excellent for a laptop) Unified memory, portability, silent operation

Use Case 1: Personal AI Chat Assistant (7B-13B Models)

For daily interactive use like coding assistance, creative writing, or summarization, a 7B or 13B model is typically sufficient. All three options perform admirably here. The RTX 3090 offers the fastest token generation, but the RTX 4070 is close enough for human perception and does so with less power. The M3 Max provides a fantastic, silent experience, making it ideal for a desk setup or on the go.

Use Case 2: Advanced RAG and Document Analysis (30B+ Models)

When dealing with large codebases, extensive research documents, or complex Retrieval Augmented Generation (RAG) systems, larger models become essential for better contextual understanding and reduced hallucination. Here, the 24GB VRAM of the RTX 3090 truly shines, allowing it to comfortably host 30B Q4_K_M models at highly usable speeds. An RTX 4070 would struggle, requiring significant CPU offloading, which slows down inference. The M3 Max (especially with 48GB+ unified memory) is also a strong contender, uniquely enabling 30B models on a laptop.

Use Case 3: Local Development and Fine-Tuning

For fine-tuning smaller models (LoRA) or experimenting with model architecture, NVIDIA’s CUDA ecosystem still offers the broadest support and the most mature tools. The RTX 3090’s 24GB is invaluable for QLoRA fine-tuning up to 30B models. While Apple’s MLX framework is rapidly maturing, not all research code or cutting-edge libraries port directly, often requiring workarounds. For pure inference, the M3 Max is competitive, but for training, NVIDIA maintains an edge in tool compatibility.

The Bottom Line: Choosing Your Local AI Champion

The “best” hardware for local AI in 2026 isn’t a single answer; it depends entirely on your priorities and budget. Each of our contenders carves out a distinct niche:

NVIDIA RTX 4070 (The Balanced Choice): If you’re building a new desktop system and prioritize power efficiency, modern features (like AV1 encoding, DLSS 3.5 for gaming), and a solid experience with 7B-13B models, the RTX 4070 is an excellent choice. It’s a reliable workhorse for everyday local AI tasks without breaking the bank or your electricity bill. However, its 12GB VRAM is a hard limit for serious 30B+ model usage.

NVIDIA RTX 3090 (The VRAM Bargain Hunter’s Dream): For those who need maximum VRAM on a budget and don’t mind buying used, the RTX 3090 is arguably the best price-to-performance option for serious LLM work. Its 24GB of GDDR6X memory allows it to run 30B models with ease and even make a compelling attempt at 70B models, a feat almost impossible on any other consumer card below $1500. Its higher power draw and older architecture are tradeoffs, but for raw LLM capacity, it’s hard to beat.

Apple M3 Max (The Portable Powerhouse): If portability, silent operation, and a tightly integrated ecosystem are paramount, the Apple M3 Max is in a league of its own. Its unified memory allows it to load models that would choke many NVIDIA cards in its price range, providing an unparalleled experience for developers on the go. While its raw tokens/second might not always match the fastest NVIDIA GPUs for smaller models, its ability to handle massive models within a laptop form factor is revolutionary. The caveat remains ecosystem lock-in for specific ML frameworks.

In 2026, the era of accessible local AI is fully upon us. The days of needing a server rack for powerful language models are over. Whether you opt for the efficiency of an RTX 4070, the sheer VRAM of a used RTX 3090, or the elegant portability of an Apple M3 Max, a world of powerful, private, and customizable AI awaits on your local machine. The ROI versus cloud APIs, especially for sensitive data or frequent use, is increasingly undeniable. Consider that a single RTX 3090 investment pays for itself within months of daily use, while cloud subscriptions accumulate indefinitely. Invest in the hardware that matches your workflow, and unlock the next generation of personal computing right on your desktop today.

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This article was produced with the assistance of AI tools and reviewed by the AIStackDigest editorial team.

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