Does CPO kill M8/M9 CCL upgrades — or is that scale-out/scale-up confusion?

Opening

Pu has the better of the near-term claim: CPO-as-copper-killer is a rumor ahead of board-level evidence. @freearkshaw relays a market view that CPO on AI servers/switches shifts high-speed signals copper→optical, reducing M8/M9 ultralow-loss CCL demand (even M4 downspecs) and pressuring CCL equities. @sssjeffpu replies that the thesis is theoretically neat but practically wrong near-term: CPO will not hit the compute board soon, and next-year NVSwitch NPO/CPO still uses higher-spec CCL (PTFE + M8/9) — PTFE remains the key thesis. Visible Chinese-language replies lean "far worry, not near worry." Deep tail unread (top-replies).

Sides

FOR — CPO substitution reduces high-end CCL / copper SerDes demand (market rumor)

• @freearkshaw [pseudo] — relays rumor: CPO near ASIC shortens PCB copper runs; 448G generation accelerates optical-for-copper; M8/M9 demand down, possible M4 downspec; CCL board selloff

AGAINST — CCL upgrade path intact near-term (named semis research)

• @sssjeffpu [named] — CPO not on compute board soon; NVSwitch NPO/CPO next year still higher-spec CCL (PTFE + M8/9); PTFE thesis stands
• @hanqing1120 [anon] — market treated scale-out optical substitution as scale-up copper substitution; CPO volumes still small — "远虑不是近忧"

Room: named Asia semis voice (Pu) vs rumor relay + A-share tape commentary; no OEM BOM primary in the visible thread.

Quotes

市场传出观点：CPO 逐步导入 AI 服务器、交换机，高速信号由铜转光，会降低对 M8/M9 超低损耗 CCL 需求，主板规格甚至可下修至 M4；该传言引发盘中覆铜板板块卖压。 — 投研荟 (@freearkshaw)

Re: CCL Upgrade Debate Theoretically right, but practically the CCL upgrade stays.

1. CPO won’t hit the compute board anytime soon
2. NVSwitch NPO/CPO next year still uses higher-spec CCL (PTFE + M8/9). -> Key thesis is still PTFE — Jeff Pu (@sssjeffpu)

@freearkshaw 市场把Scale-out的光替代当成了Scale-up的铜替代。CPO出货量还小，对CCL的冲击是远虑不是近忧。 — hanqing (@hanqing1120)

What would settle it

OEM / ODM BOM or SemiAnalysis-style teardown showing compute-board CCL grade (M8/M9/PTFE vs downspec) on next NVSwitch / Rubin-class platforms Knowable — next public teardowns / supplier commentary — through 2026-12-15

Public CPO attach rates on AI server vs switch (scale-up vs scale-out) with timing that could move CCL mix in 2026–27 Knowable — supplier earnings / industry maps — through 2026-12-15

Whether Taiwan/China CCL equity moves reverse on primary evidence rather than rumor screenshots Knowable — next 1–2 earnings cycles for major CCL names — through early 2027