ZBook Power G11a - Caps Lock/Num Lock 4-blink issue

[6G72M]

Hello HP Community,

I would like to report a reproducible boot behavior on my HP ZBook Power G11 AMD workstation.

System configuration:

• Model: HP ZBook Power G11 AMD
• CPU: AMD Ryzen 9 8945HS
• GPU: NVIDIA RTX 2000 Ada
• RAM: 32GB DDR5 (single module)
• SSD: 1TB
• LTE module installed

The issue:

During a cold boot (shutdown → power on), the following sequence happens:

1. Power button LED turns on.
2. Mute button LED turns on.
3. Caps Lock and Num Lock LEDs blink 4 times.
4. The Mute LED and Caps/Num Lock LEDs turn off.
5. Only after that, the fan starts spinning.
6. A few seconds later, the HP logo appears and the system boots normally.

The computer always starts successfully. There is no crash or failure after booting.

The same behavior also appears after opening the lid from sleep: the display takes around 2-3 seconds before turning on.

Troubleshooting already performed:

• Updated BIOS to the latest version.
• Downgraded BIOS versions to 1.09.x.
• Restored BIOS factory defaults.
• Changed Graphics setting between UMA and Hybrid.
• Reinstalled drivers.
• Removed and reseated the RAM.
• Tested the RAM in another slot.
• Used a single 32GB RAM module.

None of these steps solved the issue.

HP On-site Support experience:

I contacted HP Support and demonstrated the issue through a video call.

HP Support:

• Reinstalled drivers.
• Restored BIOS settings.
• Confirmed that the issue was still reproducible.
• Arranged an on-site technician.

The technician replaced the motherboard.

After the motherboard replacement, the issue disappeared with the factory BIOS version.

However, after updating the BIOS again, the same 4-blink behavior returned.

After downgrading to BIOS version 01.08:

• The first boot showed the 4-blink behavior.
• The second boot was normal.

This makes me suspect that the issue may be related to BIOS/EC firmware behavior rather than a hardware failure.

Could anyone confirm whether this behavior is known on ZBook Power G11 AMD models?

Is there any recommended BIOS version or EC firmware update that addresses this issue?

Thank you.

[Jerry_57 · Accepted solution]

Hi @6G72M,

Welcome to the HP Support Community.
 

Thank you for posting your query. I will be glad to help you.
 

Based on the troubleshooting you've already completed, the behavior you described points more toward BIOS/Embedded Controller (EC) firmware initialization than a hardware fault. The fact that the issue disappeared after the motherboard replacement, then returned after updating the BIOS, strongly suggests a firmware-related change rather than a defective system board.

Recommended Next Steps

1. Keep the BIOS updated to the latest HP-recommended version, as future releases may include improvements to POST and EC initialization. Official HP® Support.
    
2. Run HP PC Hardware Diagnostics UEFI to verify that the system board, memory, and other hardware pass all tests. This helps confirm there is no underlying hardware issue. HP PC Hardware Diagnostics | HP® Support.
    
3. Monitor HP BIOS release notes for updates that mention POST, firmware, or system stability improvements for the ZBook Power G11 AMD platform.

What to Expect

Since the notebook completes POST successfully, boots into Windows normally, and the behavior is consistently reproducible across BIOS versions, it is unlikely to indicate an imminent hardware failure. At present, there is no documented BIOS version or standalone EC firmware update specifically addressing this 4-blink startup behavior on the HP ZBook Power G11 AMD.

If HP releases a BIOS update that resolves this firmware behavior, installing that version would be the recommended solution.

I hope this helps.

Take care and have a great day.

[6G72M]

Hi Jerry,

Thank you for your explanation.

I would like to add one more observation that may be helpful for future troubleshooting.

According to the HP LED blink code documentation, a 4-time Caps Lock/Num Lock blink pattern is associated with a graphics controller failure. However, in my case, the system does not show the typical symptoms of a graphics failure:

• The notebook completes POST successfully.
• Windows starts normally.
• The issue is only observed during the early boot initialization phase, before the fan starts spinning and before the HP logo appears.

Since the same 4-blink pattern was reproduced after the BIOS update on a replacement system board, this case may help distinguish between an actual graphics hardware failure and a possible BIOS/EC initialization behavior.

I hope this information can help HP support engineers and technicians quickly narrow down the root cause when encountering similar cases in the future.

Thank you.

[Jerry_57]

Thank you for sharing this thoughtful observation. Your clear notes on the 4‑blink pattern and its unique behavior are invaluable. I’ll ensure your findings reach our support engineers to help pinpoint the root cause faster and make the boot experience smoother in future cases.