Mac Studio M5 Ultra 512GB 512GB provides room for workloads that do not fit in 256GB—not inherently faster memory.
Apple says the 512GB unified-memory configuration will arrive in late October 2026, but its Korean price has not been confirmed in public materials. Both the 256GB and 512GB options use the 36-core CPU and 80-core GPU configuration with 1.2TB/s memory bandwidth. If your model and prompt cache fit comfortably in 256GB, consider whether waiting for twice the capacity will actually help your work.
Hardware core specifications
- available memory
- 480GB
- Memory bandwidth
- 1200GB/s
- Estimated sustained LLM load
- About 330W
- Korean price range (KRW)
- Official 512GB price not yet announced
a person who fits well
- Model files and prompt caches that will not fit in 256GB
- Long contexts and multiple simultaneous workloads
- Large unified-memory capacity in one Mac
In this case skip it
As of September 2026, the 512GB configuration has not launched and its exact Korean price is unconfirmed. Apple's M5 Ultra starting price of KRW 9.49 million applies to the entry 96GB configuration, not the 512GB option. More memory also does not make CUDA-only serving tools or extensions run on macOS.
Recommended format for each device 4K input
The model you will experience with this equipment
MiniCPM5-2B
Required 2.07GB · spare time
MLX 4-bit
Decode
579.9 ~ 644.3 tok/s
First token
0.66 to 1.2 seconds
Qwen3.8-Flash-Next
recommendedRequired 107.43GB · spare time
MLX 4-bit · MTP
Decode
45.9 ~ 79.8 tok/s
First token
2.6 to 4.5 seconds
GLM-5.3-Flash (MoE)
Required 190.21GB · spare time
MLX 4-bit
Decode
81.3 ~ 90.3 tok/s
First token
15.0 ~ 26.1 s
Actual speed may vary depending on runtime version, cooling status, context length and quantization file.
purchase judgment
What tasks is it suitable for?
Loading very large models
ConditionalCheck the actual converted file, quantization, KV cache, and runtime support—not just the parameter count. A large memory capacity does not guarantee that every model will run.
Long documents and simultaneous workloads
SuitableRemaining memory after loading a model can support a longer prompt cache or parallel jobs. Compare throughput across requests separately from token generation speed for one request.
Models that already fit in 256GB
Not recommendedWith the same 36-core CPU, 80-core GPU, and 1.2TB/s bandwidth, doubling memory capacity does not double generation speed for the same workload. Check the capacity you actually need first.
- The first thing to get stuck
- 512GB is the total unified-memory capacity. macOS, open apps, model weights, and the KV cache all share it. The site's 480GB usable-memory figure is a planning allowance, not an Apple-guaranteed GPU allocation. If the same model already fits comfortably in 256GB, moving to 512GB will not raise generation speed in proportion to capacity.
- Configuration to check
- M5 Ultra · 36-core CPU · 80-core GPU · 512GB unified memory · 2TB or larger SSD option · Check the configuration price after launch
- Criteria for spending more money
- Start by listing the model file's quantization and size, the context length you need, and the apps you will run alongside it. Waiting for 512GB makes sense only when those demands exceed the practical headroom of a 256GB configuration. For a workload that already fits in 256GB, compare time to first token and generation speed under the same conditions before paying for capacity. Reassess the price difference once the exact 512GB price is published.
Check the 512GB configuration price after launch.
The published M5 Ultra starting price is not the 512GB configuration price. Apple plans to release this option in late October.
Frequently Asked Questions
- How much does the M5 Ultra 512GB cost?
- Apple says the 512GB configuration will launch in late October 2026, but its Korean price has not yet been confirmed. The KRW 9.49 million starting price is for the entry M5 Ultra configuration.
- Which local LLM can be run on the Studio M5 Ultra 512GB?
- You can compare MiniCPM5-2B, Qwen3.8-Flash-Next, GLM-5.3-Flash (MoE), etc. with 4K input and recommended formats. Memory requirements vary depending on model and context length.
- What is the local LLM power of the Studio M5 Ultra 512GB?
- Expected to consume approximately 330W under sustained load, with an actual range estimated between 240–460W.
- Are the displayed token speeds ground truth?
- This is an estimated range calibrated to the calculator against official hardware specifications and verified benchmark ranges. Runtime, cooling, quantization may vary depending on file and context length.
Equipment to compare together
Same chip, half the memory
Studio M5 Ultra 256GB
Provides 1,200 GB/s (1.2 TB/s) aggregate bandwidth and 256 GB of memory. Extra-large MoEs are considered for single-device loading only if compatible archives and runtimes are confirmed.
When 128GB is enough
Studio M4 Max 128GB
It is suitable for users who want to compare widely from single finished products to 70B class and high-precision models.
When CUDA tools are essential
DGX Spark 128GB
This is for working with a large model on one machine rather than splitting it across graphics cards. You need a reason to buy 128GB of capacity. If your intended model fits in 24GB or 32GB, do not expect Spark to be faster just because it has more memory.