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M5 Ultra Mac Studio Review

269 points · 262 comments · piotrgrabowski

  1. simonw · · focus · HN ↗
    The numbers I was most interested in are tucked away in a chart towards the bottom - the speed comparison of the Mac Studios v.s. a RTX 5090:

      Qwen3.8 27B tokens/sec generation speed
    
      Prompt size    8K    64K   128K   256K
      RTX 5090 PC    59    51    44     n/a
      M5 Ultra       48    39    32     24
      M3 Ultra       31    23.5  20     15
    
    A whole bunch more comparison numbers in this section: <a href="https:&#x2F;&#x2F;www.macstories.net&#x2F;stories&#x2F;m5-ultra-mac-studio-review-the-dream-mac-for-local-ai-agents&#x2F;#mx-pc" rel="nofollow">https:&#x2F;&#x2F;www.macstories.net&#x2F;stories&#x2F;m5-ultra-mac-studio-revie...
    1. karmakaze · · focus · HN ↗
      I really appreciate seeing these dense model numbers. For a large unified memory system though I expect that MoE numbers are what people are more interested in.

      These numbers could and should get much better. As an example I can run Qwen3.8-27B-MXFP4 (W4A8) on 2x AMD R9700 that gets 260+ tokens&#x2F;sec to start and slows down to ~110 tokens&#x2F;sec over 128k context and can do the max 256k. These are for batch size 1 and throughput goes higher with batching. This is due to speculative decoding, efficient all-reduce inter-gpu compression, and custom GEMM kernels for the specific hardware. Note each R9700 only has 644 GB&#x2F;s memory bandwidth.

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