CPU Microcode Update Failed – Fix Boot Error Now

You're stuck on a black screen or a boot loop

I know this error is infuriating. One day your PC boots fine, the next day it stops cold with “CPU microcode update failed” or a similar message. I've seen this on Dell laptops with Intel 12th-gen chips and on Ryzen 5000-series desktops. The fix is usually simple once you know where to look.

The real fix: update your BIOS

Skip everything else—go straight to your motherboard or laptop manufacturer's support page. Download the latest BIOS version for your exact model. Don't use beta BIOS files unless you're comfortable resetting CMOS.

Step-by-step for most users

Check your current BIOS version. On Windows, open Command Prompt and type:
```
wmic bios get smbiosbiosversion
```
On Linux, run:
```
sudo dmidecode -s bios-version
```
Go to your manufacturer's site. For ASUS, Gigabyte, MSI, Lenovo, Dell—they all have a support/downloads section. Enter your product serial number or model name.
Download the latest non-beta BIOS. Look for release notes that mention “CPU microcode update” or “stability fixes.”
Copy the BIOS file to a FAT32-formatted USB stick. Some newer boards let you update from within the BIOS (EZ Flash, M-Flash, Q-Flash). Use that option if available.
Reboot and enter BIOS setup (usually F2, Del, or F10). Find the update tool, select your USB drive, and run the update. Don't turn off your PC during this—it can brick the board.

After the update, save and exit. The system may reboot once or twice. If you get a “microcode update failed” message again, check that your CPU is fully seated and the cooler isn't overtightened. I've seen bent pins cause this too.

A guy on Reddit had the same error on an MSI Z690 board. He skipped BIOS updates for two years. A single update fixed the microcode loading issue and also stopped random USB disconnects.

Why this works

CPU microcode is firmware inside your processor that fixes bugs and helps the OS talk to the CPU correctly. The motherboard's BIOS stores the microcode patches. When you boot, the BIOS loads a patch into the CPU. If the patch is corrupted, outdated, or missing, the CPU can't start right.

Manufacturers release BIOS updates exactly to fix these problems. For example, Intel's 13th and 14th-gen chips had a microcode bug that caused instability. AMD's Zen 2 and Zen 3 chips also got microcode patches for sleep state issues. A fresh BIOS includes the latest microcode from Intel or AMD, and the error goes away.

Less common variations you might see

Sometimes the error message is different. Here are a few I've run into:

“Microcode update failed – reverting to previous version”

This usually means your BIOS tried to load a patch that doesn't match your CPU's stepping (revision). The fix is the same—BIOS update. But you can also check if your CPU is a newer revision that the current BIOS can't handle. Look up your CPU's stepping with CPU-Z or dmidecode, then compare with the BIOS release notes.

Error on Linux boot: “microcode: failed to load file /lib/firmware/amd-ucode/...”

Here the problem is the OS, not the BIOS. The Linux kernel needs microcode files in the /lib/firmware directory. You can fix it by installing the amd64-microcode or intel-microcode package:

sudo apt install amd64-microcode   # for AMD
sudo apt install intel-microcode    # for Intel

Then run sudo update-initramfs -u and reboot.

Windows Event Viewer shows “CPU microcode update failed (0x8007025D)”

This code means the BIOS didn't apply a patch during boot. It's often a driver or firmware mismatch. Try updating your chipset drivers from the motherboard site, then re-check BIOS.

How to prevent this from happening again

Update your BIOS once a year. Set a reminder. Manufacturers push fixes for security and stability.
Don't use beta BIOS unless you're troubleshooting a specific problem. Beta versions often have experimental microcode.
Keep your OS updated. Windows Update and Linux package managers deliver their own microcode patches. If the BIOS patch fails, the OS can sometimes load one.
Check your CPU's compatibility when buying a motherboard. Some older boards need a BIOS update before they support newer CPUs. That's a common CPU microcode update failed scenario.

That should get you back up and running. If you still see the error after these steps, you might have a CPU hardware issue. Try reseating the CPU or testing with a different one if you can borrow it.