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A PCIe device is detected on some boots but not others on a custom Compute Module carrier. How can software configuration, reset timing and board-level signal integrity be separated during diagnosis?
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A Compute Module carrier has intermittent PCIe detection: what should be checked first?
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Latest activity · 27 Sep 2026A Compute Module carrier has intermittent PCIe detection: what should be checked first?
Re: A Compute Module carrier has intermittent PCIe detection: what should be checked first?
#2Confirm that the exact module, endpoint and software configuration support the intended link. Capture boot logs and distinguish absence of link training from a driver that fails after enumeration. Verify endpoint power and reset sequencing against both devices' requirements.
Re: A Compute Module carrier has intermittent PCIe detection: what should be checked first?
#3Compare the carrier routing, connectors, clock arrangement and return paths with the manufacturer's design guidance. Check whether temperature, cable position or supply loading changes the failure rate. Do not treat a forced higher link speed as a diagnostic shortcut for an unstable physical link.
Re: A Compute Module carrier has intermittent PCIe detection: what should be checked first?
#4Use a known-good endpoint or reference carrier to isolate one side where possible. Make one controlled change at a time and repeat enough cold and warm boots to assess it. A single successful enumeration after a modification does not establish a reliable fix.