ASUS ROG Maximus Z890 Hero - ERROR 55 - Boot impossible

[PhilouJ]

I have just bought and equipped my new PC with an ASUS ROG Maximus Z890 Hero motherboard.
I equipped it with 4 Corsair Vengeance RGB DDR5 128 GB (4 x 32 GB) 5600 MHz CL40 RAMs.
I've checked compatibility with the motherboard and all is OK.

I've updated the BIOS to the latest version available on the ASUS ROG website and nothing changes, still the same error 55 ?

What can I do?

Thnaks for your feedback

[Jiaszzz_ROG]

Hello @PhilouJ 

Thank you for reaching out to us.
According to [Motherboard] Common Q-CODE(Error CODE) and Troubleshooting, a failure to pass POST and the appearance of Q-code 55 on an Intel-based motherboard typically indicate a memory detection issue.
Could you confirm if the memory module currently installed is CMH128GX5M4B5600C40? If you install a single memory module in the DIMM_A2 slot, are you able to boot into the BIOS?

If your installed memory does not match this part number, we recommend cross-testing with a memory module listed in the QVL for compatibility.
For more details, please refer to [Motherboard] How to query (CPU/memory) QVL List? and the "purchasing and installation guide" section on QVL page.

Thank you.