NIEK2-0328
① SA Source
- Source: 開啟完整 SA 文章
- Section:
Feynman NVL1152 Networking Topologies - Line hint:
399
Context Before
Feynman NVL1152 Networking Topologies
Within each Feynman Kyber rack, we tentatively assume double the bandwidth per logical GPU and double the NVLink Switch bandwidth to 28.8T and 57.6T respectively. Though Jensen, in the Financial Q+A the day after the GTC Keynote, characterized NVL1152 as “all CPO”, the key technical blog outlining the new rack form factors ↗ only strictly referenced CPO for rack to rack interconnect. We will discuss the potential topography for both options.
Evidence
To double the scale-up bandwidth using copper interconnect, NVIDIA would have to achieve a per lane bandwidth of 448Gbit/s uni-di (and implemented with simulatanous bi-directional SerDes so that each physical channel carries 448G of RX and 448G of TX) . However, this is a challenging feat as they would first have to prove the feasibility of 448Gb/s PAM4 SerDes at large volumes, then implement echo cancellation to achieve bidirectional bandwidth ↗, which is in itself extremely difficult. We believe Nvidia is going for 448G uni-di only.
Context After
Source: SemiAnalysis
② Atomic Claim
但這非常困難，因為首先必須證明 448Gb/s PAM4 SerDes 可大規模量產，再導入 echo cancellation 以實現雙向頻寬，而後者本身也極具挑戰。
- Epistemic Mode:
ASSERTED - Mapping Status:
PARTIAL
③ Semantic Frame
{
"frame_type": "NARY_RELATION",
"participants": [
{
"node": {
"id": "04_knowledge_base/PAM4",
"label": "PAM4"
},
"role": "subject"
},
{
"node": {
"id": "04_knowledge_base/SerDes",
"label": "SerDes"
},
"role": "participant"
},
{
"node": {
"id": "04_knowledge_base/Echo cancellation",
"label": "echo cancellation"
},
"role": "participant"
}
],
"qualifiers": {
"condition_text": null,
"numeric_mentions": [
"448Gb/s"
],
"temporal_mentions": []
},
"relation_type": "RELATED_TO"
}④ Canonical Entity Mapping
| Role | Surface Label | Canonical Target |
|---|---|---|
| subject | PAM4 | PAM4 |
| participant | SerDes | SerDes |
| participant | echo cancellation | 04_knowledge_base/Echo cancellation |
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。