PCR0 Measured Boot mismatch on Windows 11 despite TPM and Secure Boot being enabled

Hello,

I would like to report a possible Windows 11 Measured Boot / attestation inconsistency on my platform and ask whether anyone from Microsoft or the community has seen a similar pattern.

This is not mainly a game-support post. A third-party service relying on attestation exposed the issue, but the underlying problem appears to be at the Windows / platform attestation level.

System / platform:

- MSI Raider GE78 HX

- Model: MS-17S1

- Intel 14th Gen platform

- TPM enabled and present

- Secure Boot enabled

- BIOS updated to latest available version

- BIOS also re-tested through downgrade / re-update paths

Windows-side observations:

- HealthStatus: Possibly attestable

- PcrsMatchTcgLog: false

- BitMaskOfPcrMismatches: 1

This points to a likely PCR0-related mismatch.

Independent cross-check:

To verify whether this might be limited to my Windows installation, I also performed a Linux live USB cross-check.

Linux results:

- TPM access worked

- firmware TPM event log parsing worked

- PCRs 1 through 7 matched between the live TPM values and the event-log replay

- PCR0 did not match

So the pattern appears to be:

- PCR 1-7: match

- PCR0: mismatch

Additional context:

MSI has already reviewed this extensively and has reproduced related behavior internally on the same platform. According to MSI, improper BIOS settings do not appear to be the root cause, and they believe the platform meets the disclosed baseline requirements from the software side that relies on attestation.

MSI also indicated they are coordinating with Microsoft, Intel, and the affected third party because the issue may involve platform recognition / attestation handling on newer TPM / CPU combinations.

What I am trying to understand:

- Has Microsoft seen similar Measured Boot / PCR replay inconsistency on newer Intel platforms?

- Could this relate specifically to PCR0 / CRTM measurement behavior?

- Is there any known issue involving newer Intel generations, TPM firmware identification, or Secure Boot 2023 CA / attestation behavior?

If useful, I can also share sanitized screenshots of:

- tpm.msc

- Event Viewer entries

- the attestation-related logs

- Linux event-log replay output

Any guidance would be appreciated.

Kind regards,

Aylinka123