VR2-0582

① SA Source

  • Source: 開啟完整 SA 文章
  • Section: GB200 Hardware Architecture - Component Supply Chain & BOM
  • Line hint: 703

Context Before

Read full story

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. As such, in order to deliver double the aggregate scale-up bandwidth required for NVLink 6, Vera Rubin NVL72 racks will contain double the number of NVLink Switches as compared to GB200 racks. This translates to four NVLink Switch chips per tray on 9 switch trays, or 36 NVLink Switch chips in each rack.

Evidence

As such, all NVLink signals will run over the PCB

Context After

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.

image

② Atomic Claim

因此,所有 NVLink signals 都會走 PCB

  • Epistemic Mode: ASSERTED
  • Mapping Status: PARTIAL

③ Semantic Frame

{
  "attribute": "UNSPECIFIED_ATTRIBUTE",
  "context_nodes": [
    {
      "id": "04_knowledge_base/PCB",
      "label": "PCB"
    }
  ],
  "entity": {
    "id": "04_knowledge_base/NVLink",
    "label": "NVLink"
  },
  "frame_type": "ATTRIBUTE",
  "qualifiers": {
    "condition_text": null,
    "numeric_mentions": [],
    "temporal_mentions": []
  },
  "value": {
    "numeric_mentions": [],
    "value_text": "因此,所有 NVLink signals 都會走 PCB。"
  }
}

④ Canonical Entity Mapping

RoleSurface LabelCanonical Target
entityNVLinkNVLink
context_0PCBPCB

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。