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Mac Studio M3 Ultra 256GB vs NVIDIA RTX PRO 6000 Blackwell

For running models locally, priced in the US. At 128k context the first runs 42 models fully in memory, the second 39.

In short

The Mac Studio M3 Ultra 256GB has more memory for models: 256 GB against 96 GB. At 128k context the Mac Studio M3 Ultra 256GB runs 42 of the models we track fully in memory and the NVIDIA RTX PRO 6000 Blackwell 39; only the Mac Studio M3 Ultra 256GB holds DeepSeek V4 Flash. On the models both run fully in memory, the NVIDIA RTX PRO 6000 Blackwell is about 2.1× as fast as the Mac Studio M3 Ultra 256GB (estimated, median across models). In the US the Mac Studio M3 Ultra 256GB costs $8,499 at eBay and the NVIDIA RTX PRO 6000 Blackwell $8,000 at Amazon: the NVIDIA RTX PRO 6000 Blackwell is $499 cheaper.

Updated . Speeds are estimates; how they are worked out.

Mac Studio M3 Ultra 256GB

$8,499

eBay

Add to build
NVIDIA RTX PRO 6000 Blackwell

$8,000

Amazon

Add to build

Specifications

SpecMac Studio M3 Ultra 256GBNVIDIA RTX PRO 6000 Blackwell
ChipApple M3 Ultra (80-core GPU)–
Memory bus1024-bit512-bit
Memory bandwidth819 GB/s1,792 GB/s
FP16 compute28 TFLOPS504 TFLOPS
SoftwareMetalCUDA
Unified memory256 GB–
GPU can use by default192 GB–
GPU can use, tuned248 GB–
Operating systemmacos–
ProcessorM3 Ultra 32-core–
Storage2000 GB–
GPU–RTX PRO 6000 Blackwell
Memory–96 GB GDDR7
Board power–600 W
PCIe generation–Gen 5
PCIe lanes–x16

What each runs

Estimated decode speed with the most precise quant that fits each one est.

ModelMac Studio M3 Ultra 256GBNVIDIA RTX PRO 6000 Blackwell
DeepSeek V4 Flash14tok/sUD-Q4_K_XLoffload
GLM 5.3 Flash18tok/sUD-Q4_K_XLoffload
Qwen 3.8 Flash Next5tok/sQ8_020tok/sUD-Q3_K_XL
Qwen 3.8 27B14tok/sQ8_029tok/sQ8_0
MiniMax M2.78tok/sUD-Q5_K_Moffload
Qwen 3.5 122B-A10B23tok/sQ8_062tok/sQ5_K_M
Qwen 3.6 27B14tok/sQ8_030tok/sQ8_0
Qwen3 Coder Next43tok/sQ8_090tok/sQ8_0
gpt-oss 120B40tok/sMXFP484tok/sMXFP4
Nemotron 3 Super 120B-A12B23tok/sQ8_072tok/sUD-Q4_K_M
Gemma 4 31B12tok/sQ8_025tok/sQ8_0
Mistral Small 4 119B30tok/sQ8_080tok/sUD-Q5_K_M
Qwen 3.6 35B-A3B55tok/sQ8_0114tok/sQ8_0
Qwen 3.5 27B14tok/sQ8_030tok/sQ8_0
Gemma 4 26B-A4B45tok/sQ8_095tok/sQ8_0
GLM 4.5 Air8tok/sQ8_019tok/sQ4_K_M
Qwen 3.5 35B-A3B55tok/sQ8_0114tok/sQ8_0
Qwen3 Next 80B-A3B50tok/sQ8_0104tok/sQ8_0
GLM 4.7 Flash26tok/sQ8_054tok/sQ8_0
Devstral Small 2 24B11tok/sQ8_024tok/sQ8_0
Nemotron 3.5 Lightning 30B-A3B76tok/sUD-Q6_K_XL160tok/sUD-Q6_K_XL
Kimi Linear 48B-A3B75tok/sQ8_0155tok/sQ8_0
gpt-oss 20B57tok/sMXFP4118tok/sMXFP4
Qwen3 Coder 30B-A3B20tok/sQ8_042tok/sQ8_0
Qwen3 32B8tok/sQ8_016tok/sQ8_0
Gemma 4 12B35tok/sQ8_073tok/sQ8_0
Qwen 3.5 9B38tok/sQ8_080tok/sQ8_0
Gemma 3 27B13tok/sQ8_028tok/sQ8_0
Mistral Small 3.2 24B11tok/sQ8_024tok/sQ8_0
DeepSeek R1 Distill Qwen 32B8tok/sQ8_016tok/sQ8_0
Llama 3.3 70B5tok/sQ8_012tok/sQ5_K_M
Ministral 3 14B15tok/sQ8_031tok/sQ8_0
Qwen3 14B14tok/sQ8_030tok/sQ8_0
DeepSeek R1 0528 Qwen3 8B19tok/sQ8_040tok/sQ8_0
Qwen3 8B19tok/sQ8_040tok/sQ8_0
Phi-4 14B13tok/sQ8_026tok/sQ8_0
Qwen 3.5 4B60tok/sQ8_0126tok/sQ8_0
Ministral 3 8B20tok/sQ8_041tok/sQ8_0
Granite 4.2 8B17tok/sQ8_036tok/sQ8_0
Gemma 4 E4B44tok/sQ8_093tok/sQ8_0
LFM2.5 8B-A1B43tok/sQ8_089tok/sQ8_0
Llama 3.1 8B22tok/sQ6_K47tok/sQ6_K

Questions

Which is better for local AI, the Mac Studio M3 Ultra 256GB or the NVIDIA RTX PRO 6000 Blackwell?
Choose the Mac Studio M3 Ultra 256GB to run bigger models. Choose the NVIDIA RTX PRO 6000 Blackwell for speed. Choose the NVIDIA RTX PRO 6000 Blackwell to spend less.
Which can run bigger models, the Mac Studio M3 Ultra 256GB or the NVIDIA RTX PRO 6000 Blackwell?
At 128k context the Mac Studio M3 Ultra 256GB runs 42 of the models we track fully in memory and the NVIDIA RTX PRO 6000 Blackwell 39; only the Mac Studio M3 Ultra 256GB holds DeepSeek V4 Flash.
Which is faster for local AI, the Mac Studio M3 Ultra 256GB or the NVIDIA RTX PRO 6000 Blackwell?
On the models both run fully in memory, the NVIDIA RTX PRO 6000 Blackwell is about 2.1× as fast as the Mac Studio M3 Ultra 256GB (estimated, median across models).
What is the price difference between the Mac Studio M3 Ultra 256GB and the NVIDIA RTX PRO 6000 Blackwell?
In the US the Mac Studio M3 Ultra 256GB costs $8,499 at eBay and the NVIDIA RTX PRO 6000 Blackwell $8,000 at Amazon: the NVIDIA RTX PRO 6000 Blackwell is $499 cheaper.

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