clm_cda1035511f947c2a8583b8a091a6a72_r1

VR2-0577

① SA Source

• Source: 開啟完整 SA 文章
• Section: GB200 Hardware Architecture - Component Supply Chain & BOM
• Line hint: 701

Context Before

2024年7月17日

Read full story ↗

Evidence

Although the NVLink 6 Switch used in the VR NVL72 system delivers the same per switch 28.8T aggregate bandwidth as NVLink 5 Switch, the SerDes speed on the NVLink 6 Switch is double the SerDes speed of NVLink 5 Switch but with the same number of DPs

Context After

Each VR NVL72 Switch tray contains four NVLink 6 Switch ASICs and one system management module. The design of the Rubin NVLink 6 Switch tray is also simpler and relatively seamless compared to the first Oberon NVLink 5 Switch released for GB200 because Rubin NVLink 6 Switch trays will not use flyover cables. As such, all NVLink signals will run over the PCB.

The NVLink 6 Switch board is liquid cooled and will be covered with a cold plate, which is a single module. Connected to the NVSwitch tray is the system management module (SMM) that comes with a CPU and acts as a host to the switch tray. The switch tray to SMM connection uses flyover cables, but this is the only flyover cable connection required in the entire Vera Rubin NVL72 system. Given that the PCIe connection is lower speed and the NVLink Switch tray contains relatively few modules, assembly of the switch tray is unlikely to be challenging.

② Atomic Claim

雖然 VR NVL72 使用的 NVLink 6 Switch，每顆 switch aggregate bandwidth 仍為 28.8T、與 NVLink 5 Switch 相同，但 NVLink 6 Switch 的 SerDes speed 是 NVLink 5 Switch 的 SerDes speed 2 倍，且 DP 數量相同。

• Epistemic Mode: ASSERTED
• Mapping Status: COMPLETE

③ Semantic Frame

{
  "comparison_expression": "雖然 VR NVL72 使用的 NVLink 6 Switch，每顆 switch aggregate bandwidth 仍為 28.8T、與 NVLink 5 Switch 相同，但 NVLink 6 Switch 的 SerDes speed 是 NVLink 5 Switch 的 SerDes speed 2 倍，且 DP 數量相同。",
  "entities": [
    {
      "id": "04_knowledge_base/VR NVL72",
      "label": "VR NVL72"
    },
    {
      "id": "04_knowledge_base/NVLink",
      "label": "NVLink"
    },
    {
      "id": "04_knowledge_base/NVLink5",
      "label": "NVLink 5"
    },
    {
      "id": "04_knowledge_base/SerDes",
      "label": "SerDes"
    }
  ],
  "frame_type": "COMPARISON",
  "metric": "BANDWIDTH",
  "operator": "MULTIPLE_OF",
  "qualifiers": {
    "condition_text": null,
    "numeric_mentions": [
      "6 S",
      "28.8",
      "5 S",
      "2"
    ],
    "temporal_mentions": []
  }
}

④ Canonical Entity Mapping

Role	Surface Label	Canonical Target
comparison_entity_0	VR NVL72	04_knowledge_base/VR NVL72
comparison_entity_1	NVLink	NVLink
comparison_entity_2	NVLink 5	NVLink5
comparison_entity_3	SerDes	SerDes

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。