clm_142e493118c345f1a5786eb4cc7fd55a_r1

VR2-0608

① SA Source

• Source: 開啟完整 SA 文章
• Section: GB200 Hardware Architecture - Component Supply Chain & BOM
• Line hint: 733

Context Before

Vera Rubin NVL72 Scale-up Topology. Source: SemiAnalysis AI Networking Model ↗

While the VR NVL72 system features GPUs and scale-up switches that are connected by copper cables, the VR HGX system features servers consisting of eight Rubin GPUs and four NVLink Switch chips. The second meaningful difference between the NVL72 and HGX deployments is that the former has a scale-out bandwidth of 1.6T per GPU while the latter only has a scale-out bandwidth of 800G per GPU. How is it that all Rubin 200 deployments use CX-9 NICs even though some deployments have half the per GPU scale-out bandwidth?

Evidence

The Vera Rubin NVL72 deployment on the other hand doubles the per GPU scale-out bandwidth to 1.6T, but not by doubling the bandwidth per NIC

Context After

Each compute tray on the VR NVL72 has eight 800G CX-9 NICs, but there are two possibilities for the number of OSFP cages - either one 1.6T OSFP cage per GPU for a total of 4 per compute tray, or two 800G OSFP cages per GPU for a total of 8 cages per compute tray. We think that the latter would be the more popular deployment assumption, and will be the base case for our discussion of scale-out networking architectures in later sections of the article.

② Atomic Claim

Vera Rubin NVL72 則把每顆 GPU scale-out bandwidth 加倍至 1.6T，但並非把單顆 NIC bandwidth 加倍。

• Epistemic Mode: ASSERTED
• Mapping Status: COMPLETE

③ Semantic Frame

{
  "comparison_expression": "Vera Rubin NVL72 則把每顆 GPU scale-out bandwidth 加倍至 1.6T，但並非把單顆 NIC bandwidth 加倍。",
  "entities": [
    {
      "id": "04_knowledge_base/Vera Rubin",
      "label": "Vera Rubin"
    },
    {
      "id": "04_knowledge_base/GPU",
      "label": "GPU"
    },
    {
      "id": "04_knowledge_base/1.6T",
      "label": "1.6T"
    },
    {
      "id": "04_knowledge_base/NIC",
      "label": "NIC"
    }
  ],
  "frame_type": "COMPARISON",
  "metric": "BANDWIDTH",
  "operator": "MULTIPLE_OF",
  "qualifiers": {
    "condition_text": null,
    "numeric_mentions": [
      "1.6"
    ],
    "temporal_mentions": []
  }
}

④ Canonical Entity Mapping

Role	Surface Label	Canonical Target
comparison_entity_0	Vera Rubin	04_knowledge_base/Vera Rubin
comparison_entity_1	GPU	GPU
comparison_entity_2	1.6T	1.6T
comparison_entity_3	NIC	NIC

⑤ Human Review

請在 Properties 逐項確認：

• 原文 → Atomic Claim 是否忠實
• Atomic Claim → Semantic Frame 是否忠實
• Canonical Entity mapping 是否正確
• Epistemic mode 是否保留原文語氣
• 最後選擇 review_action

Review state

Markdown 內文不是正式 approval。只有 Apply bridge 寫入的 Decision Ledger event 才是正式決策。