Monthly Archives: May 2023

Install ESXi 8 on Intel 12th CPU – “Fatal CPU mismatch on feature”

This problem is caused by the new architecture of Intel CPUs which are equipped with different types of cores – Performance-cores and Efficient-cores.

The parameter needs to be set prior to installation and the first boot of ESXi.

  1. When ESXi installation starts, press SHIFT+O to edit boot options.
  2. Append cpuUniformityHardCheckPanic=FALSE
  3. Press ENTER
  4. Install ESXi
  5. When the installation is finished, reboot the system and press SHIFT+O to edit the boot options again.
  6. Append cpuUniformityHardCheckPanic=FALSE and press ENTER
  7. To make the kernel option permanent, run the following command on your ESXi host:
    # esxcli system settings kernel set -s cpuUniformityHardCheckPanic -v FALSE
  8. We also have to enable kernel option ignoreMsrFaults to prevent PSOD during VM startups.
    # esxcli system settings kernel set -s ignoreMsrFaults -v TRUE

This setting allows ESXi to work with different P-Cores and E-Cores