Lenovo IdeaPad Gaming 3 15ARH05 (Ryzen 5 4600H) - PSP present but no TPM exposed to Windows

Hardware Hub Laptops & Netbooks
1

Hi,

I’m trying to diagnose a TPM/fTPM issue on my Lenovo IdeaPad Gaming 3 15ARH05 with Ryzen 5 4600H.

BIOS versions tested:

  • FCCN21WW

  • FCCN16WW

Current situation:

  • AMD Platform Security Processor exists in BIOS

  • PSP device is visible in Windows

  • Secure Boot works correctly

  • System is running in pure UEFI mode

  • AMD CBS/PBS hidden menus were unlocked successfully

However:

  • Windows does not detect TPM at all

  • Get-Tpm returns TpmPresent : False

  • tpm.msc shows no TPM

  • no TPM device appears in Device Manager

  • no TPM-WMI logs are generated

I already tried:

  • enabling/disabling AMD PSP

  • loading BIOS defaults

  • BIOS downgrade/upgrade

  • reinstalling AMD PSP drivers

  • checking all AMD CBS/FCH/NBIO menus for hidden fTPM options

Interesting part:

  • many PSP/SEV/SMU options exist,

  • but there is absolutely no fTPM/Trusted Computing/AMD fTPM option anywhere in BIOS.

This makes me think:

  • BIOS/AGESA may not expose TPM ACPI interface,

  • EC firmware may block PSP TPM init,

  • or Lenovo disabled fTPM at firmware level for this board revision.

Has anyone seen this exact issue on 15ARH05 or RenoirPI-FP6 1.0.0.2?

Is there any known BIOS mod / NVRAM variable / ACPI patch / PSP fix that could restore TPM exposure?

Thanks.

3

Thanks, that confirms my suspicion.

Would it be possible to identify the hidden variable/offset responsible for enabling AMD fTPM on this model?

I already unlocked AMD CBS/PBS menus, but there is still no visible TPM/fTPM option anywhere in BIOS.

If there is a known setup variable or RU.EFI method to enable it, I’d really appreciate guidance.

4

Hi again,

I tried the GRUB setup_var method and RU.EFI.

I can read the Setup variable correctly:
GUID: A04A27F4-DF00-4D42-B552-39511302113D

Offset 0x6A returns 0x00, so it looks like fTPM is disabled.

But every write attempt fails with:
“can’t set variable using EFI (0x800000000000001a)”

I also tried:

  • setup_var

  • setup_var_3

  • setup_var_cv

  • disabling Secure Boot

Reading works, writing does not.

Looks like Lenovo/Insyde locked EFI variable writes.

Would anyone here be able to help with:

  • IFR extraction,

  • BIOS mod,

  • unlocked Setup variable access,

  • or enabling fTPM directly from BIOS dump?

I can provide BIOS files/dumps if needed.

Thanks :slightly_smiling_face: