clm_1330b3a22605461c9466ba5bd91176ae_r1

VR2-0312

① SA Source

• Source: 開啟完整 SA 文章
• Section: Relocating ConnectX-9
• Line hint: 413

Context Before

Source: Nvidia VR NVL72 Component BoM and Power Budget Model ↗

For the GB200/GB300, the PCIe signal distance between the GPU/CPU and the CX-7/8 is shorter than the Ethernet/InfiniBand signal distance between the CX-7/8 and the OSFP cages. Previously – having to transmit a 200G Ethernet/InfiniBand signal from the NIC in the back half of the compute tray to the OSFP cage in the front of the compute tray necessitated the use of flyover cables as the signal loss over PCB at 200Gbit/s (uni-directional) per lane is too high.

Evidence

By making the PCIe Gen6 signal longer, the signal can travel over PCB given that PCIe Gen6 has better signal integrity than the higher speed 200G Ethernet/InfiniBand signal

Context After

PCB vs Flyover Cables

Nevertheless, it is still challenging to drive a PCIe Gen6 signal over around 500mm of PCB distance from the Strata Module to the front of the Orchid Module. In addition to having high quality SerDes, proper signal integrity is still achievable by upgrading PCB materials.

② Atomic Claim

讓 PCIe Gen6 signal 走較長距離後，因 PCIe Gen6 的 signal integrity 優於更高速的 200G Ethernet／InfiniBand signal，因此可改由 PCB 傳輸。

• Epistemic Mode: ASSERTED
• Mapping Status: PARTIAL

③ Semantic Frame

{
  "comparison_expression": "讓 PCIe Gen6 signal 走較長距離後，因 PCIe Gen6 的 signal integrity 優於更高速的 200G Ethernet／InfiniBand signal，因此可改由 PCB 傳輸。",
  "entities": [
    {
      "id": "04_knowledge_base/PCIe",
      "label": "PCIe Gen6"
    },
    {
      "id": "04_knowledge_base/200G",
      "label": "200G"
    },
    {
      "id": "04_knowledge_base/Ethernet",
      "label": "Ethernet"
    },
    {
      "id": "04_knowledge_base/InfiniBand",
      "label": "InfiniBand"
    },
    {
      "id": "04_knowledge_base/PCB",
      "label": "PCB"
    }
  ],
  "frame_type": "COMPARISON",
  "metric": "UNSPECIFIED_METRIC",
  "operator": "OUTPERFORMS",
  "qualifiers": {
    "condition_text": null,
    "numeric_mentions": [
      "200"
    ],
    "temporal_mentions": []
  }
}

④ Canonical Entity Mapping

Role	Surface Label	Canonical Target
comparison_entity_0	PCIe Gen6	PCIe
comparison_entity_1	200G	200G
comparison_entity_2	Ethernet	Ethernet
comparison_entity_3	InfiniBand	InfiniBand
comparison_entity_4	PCB	PCB

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。