Archive for March, 2026

Minisforum MS-A2 HOW TO: Fix the Failed to Update CPU#0 Microcode PSOD with ESXi 8.0.3i ESXi 8.0u3i

Wednesday, March 11th, 2026

Minisforum MS-A2 HOW TO: Fix the Failed to Update CPU#0 Microcode PSOD with ESXi 8.0.3i ESXi 8.0u3i

 

HOW TO: Fix “Failed to update CPU#0 microcode” PSOD on ESXi 8.0.3i (Minisforum MS-A2)

In this guide from Hancock’s VMware Half Hour, I demonstrate how to fix the
Purple Screen of Death (PSOD) error:

“Failed to update CPU#0 microcode”

This issue occurs when installing or booting VMware ESXi 8.0 Update 3i (ESXi 8.0.3i)
on the Minisforum MS-A2 mini workstation.

ESXi 8.0.3i, released on 2 March 2026, includes security fixes for
CVE-2025-15467, an OpenSSL vulnerability. If you are running ESXi and have not
patched yet, you should update as soon as possible.

However, this update also includes new AMD CPU microcode updates, which currently
appear to trigger a PSOD during boot on the Minisforum MS-A2 platform.


The Problem

When booting the ESXi 8.0.3i installer (for example from Ventoy) on the
Minisforum MS-A2, the system may fail during boot with the following PSOD message:

The system has found a problem on your machine and cannot continue.

Failed to update CPU#0 microcode

This prevents ESXi from completing the boot process or installer launch.


Why This Happens

The ESXi 8.0.3i update includes newer AMD microcode updates intended to improve
security and stability. Unfortunately, these updates currently appear to be
incompatible with the MS-A2 platform, which results in the microcode update failing
during boot.

When the microcode update fails, ESXi halts the boot process and displays the PSOD.


The Workaround

Until VMware releases a permanent fix, the issue can be worked around by using a
kernel boot option during ESXi startup.

Steps to Fix

  1. Boot the ESXi 8.0.3i installer.
  2. When the ESXi boot screen appears, press Shift + O.
  3. This opens the ESXi boot options.
  4. Add the required kernel option shown in the video.
  5. Press Enter to continue booting.

With the boot option applied, ESXi should boot successfully on the Minisforum MS-A2.


Video Walkthrough

Watch the full walkthrough below where I demonstrate the issue and apply the workaround.


What You Will Learn

  • What changed in ESXi 8.0.3i
  • Why AMD microcode updates trigger a PSOD
  • How to reproduce the issue during boot
  • The Shift + O ESXi boot workaround
  • How to confirm the fix works successfully

Credits

Huge thanks to members of the VMware community who investigated and documented this issue:

  • Stephen Wagner
  • Patrick Kernstock
  • vAndu
  • Martin Gustafsson

Their research and testing helped identify the workaround shown in this video.

Resources:


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HOW TO: Create a Custom ESXi 9.0 ISO with the Realtek Driver Fling

Sunday, March 1st, 2026

 

HOW TO: Create a Custom VCF 9.0 VMware ESXi 9.0 ISO with Realtek Driver (PowerCLI)

Author: Andy – Andysworld.org.uk

Good news for homelab enthusiasts! We finally have a working Realtek network driver for ESXi 9.0. In this guide, I’ll show you step-by-step how to create a customised VMware ESXi 9.0 ISO for VCF 9.0 with the Realtek driver injected (slipstreamed) using PowerShell 7 and VMware PowerCLI.


Why This Matters

If you’re running ESXi in a homelab environment using consumer hardware, Mini PCs, or whitebox builds, Realtek NIC support has historically been a challenge. With the latest Realtek driver available, we can now build a custom ESXi 9.0 ISO that works perfectly in lab environments.

This process allows you to:

  • Inject the Realtek driver into the ESXi 9.0 image profile
  • Create a bootable ISO installer
  • Export an offline ZIP bundle

Important Disclaimer

ESXi 9.0 depot files require a valid Broadcom contract. I do not distribute depot files, customised ISOs, or any Broadcom software. Please obtain required files through official channels.


Prerequisites

  • PowerShell 7
  • VMware PowerCLI (latest version)
  • Python 3.12
  • VMware ESXi 9.0 Depot ZIP
  • VMware Realtek Driver ZIP

Method 1 – Manual Image Build (PowerCLI)

Step 1 – Load the ESXi Depot

Add-EsxSoftwareDepot .\VMware-ESXi-9.0.0.0.24755229-depot.zip

Step 2 – Load the Realtek Driver Depot

Add-EsxSoftwareDepot .\VMware-Re-Driver_1.101.01-5vmw.800.1.0.20613240.zip

Step 3 – List Available Image Profiles

Get-EsxImageProfile | Select Name

Step 4 – Clone the Standard Profile


$newProfile = New-EsxImageProfile `
-CloneProfile 'ESXi-9.0.0-14755229-standard' `
-Name 'ESXi-9.0.0-14755229-standard-Realtek-nic' `
-Vendor "Andysworld.org.uk"

Step 5 – Inject the Realtek Driver

Add-EsxSoftwarePackage -ImageProfile $newProfile -SoftwarePackage "if-re"

Step 6 – Export the Custom ISO

Export-ESXImageProfile -ImageProfile $newProfile -ExportToIso -FilePath "$($newProfile.Name).iso"

Step 7 – Export the Offline Bundle

Export-ESXImageProfile -ImageProfile $newProfile -ExportToBundle -FilePath "$($newProfile.Name).zip"

Step 8 – Verify Output

dir

You should now have both a customised ISO and ZIP bundle ready for deployment in your homelab.


Method 2 – Scripted Approach

If you prefer automation, you can use a PowerShell script to perform the entire process in one go. The script automates:

  • Loading depot files
  • Cloning image profiles
  • Injecting the Realtek driver
  • Exporting ISO and ZIP bundles

This method is ideal for repeat builds or lab rebuilds.


Who Is This For?

  • Homelab enthusiasts
  • VMware learners
  • Mini PC / Whitebox ESXi users
  • VCF 9.0 lab deployments

This guide is intended for lab and educational use only, not production environments.


Final Thoughts

Creating a custom ESXi image is a valuable skill for anyone running a VMware homelab. With the Realtek driver now available for ESXi 9.0, lab builders can continue using affordable hardware while staying current with VMware releases.

If you found this guide helpful, check out more VMware content here at Andysworld.org.uk.