Hardware⏱️ 3 min read📅 2026-05-28

How to Fix 0X3D Error – Stuck in BIOS Boot Loop after M.2 Swap on new MSI B850

BIOS Boot Loop after M.2 Swap on new MSI B850 / 9800X3D with USB Installer Rejected

Quick Answer: Try booting in UEFI mode and disable Secure Boot, then re-enable it afterwards to see if the issue persists.

The problem occurs due to the M.2 swap causing a conflict between the two drives, resulting in the BIOS boot loop. This issue is likely caused by the USB installer rejecting the Crucial T500 drive due to its different specifications compared to the Lexar drive.

⚠️ Common Causes

  • Using a different M.2 drive in the same slot.
  • Conflicting drive specifications.
  • Bios not recognizing the new drive.

🛠️ Step-by-Step Verified Fixes

Method 1: Revert M.2 Swap and Boot from Legacy Mode

  1. Step 1: Remove the Crucial T500 drive from the top slot.
  2. Insert the Lexar drive back into the top slot and boot up your PC in Legacy mode (if available).
  3. Update your BIOS to the latest version if not already done.

Method 2: Disable M.2 and Boot from USB

  1. Step 1: Enter your BIOS settings by pressing F2 (or the key indicated in your motherboard manual).
  2. Disable M.2 and set the USB drive as the primary boot device.
  3. Save changes and exit the BIOS settings.

Method 3: Perform a Clean Installation with a Different USB Installer

  1. Step 1: Create a new Windows installation media using a different USB installer (e.g., Microsoft Media Creation Tool).
  2. Insert the new USB installer and boot up your PC.
  3. Follow the on-screen instructions to install Windows.

💡 Conclusion

By following these steps, you should be able to resolve the BIOS boot loop and successfully install Windows on your MSI B850/9800X3D motherboard.

Did this fix your problem?

If not, try searching for specific error codes.

🔍 Search Error Database

❓ Frequently Asked Questions