HP Z8 G4 Not Detecting Thunderbolt 3 PCIe Card (P/N: 3UU05AA)

[mansour90]

I own an HP Z8 G4 Workstation (Product Number/SKU: 52V02EC#ABD) equipped with an HP Thunderbolt 3 PCIe Card – P/N: 3UU05AA.
I am experiencing an issue where the card is not detected at all in Windows 11 under Device Manager.
While the USB-C port on the card provides power and charges my phone, Thunderbolt functionality and PCIe data transfer are completely unavailable.

I have already performed the following steps:

1. Installed the card in the recommended PCIe Slot 1.

2. Connected the GPIO/Thunderbolt Header cable from the TB1 port on the motherboard to the 1BT_GPIO port on the card.

3. Enabled Thunderbolt settings in the BIOS and set the Security Level to “No Security”.

4. Installed the HP Thunderbolt Driver and Software for Windows 11 (SP145461).

5. Attempted to update the firmware using the HP Thunderbolt 3 Firmware Update Utility (SP143329), but the tool does not detect any Thunderbolt device.

6. Checked in both Device Manager and “Devices by Connection” view — no Thunderbolt Controller appears.

Based on this, it seems that the motherboard does not detect the card at the hardware level, even though the USB-C port is powered.
Please advise on a resolution or confirm whether the card needs repair or replacement, as all recommended troubleshooting steps have been completed without success.

[TheHelper0007]

Hello @mansour90,

It sounds like you've done a very thorough job of troubleshooting, and your methodical approach is commendable. It's indeed frustrating when you've followed all the instructions and the hardware still isn't recognized.

Based on your description, you've covered all the essential installation and configuration steps. The fact that the USB-C port provides power is a key clue, suggesting that the card is receiving some power from the PCIe slot, but the data connection, which is crucial for Thunderbolt and PCIe functionality, isn't being established.

Here are a few additional things to consider, ranging from simple checks to more involved steps:

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Double-Check the GPIO Cable Connection

While you've mentioned connecting the GPIO cable, it's worth taking another look at this specific connection. This cable is critical for the motherboard to recognize and initialize the Thunderbolt card.

• Reseat the cable: Power down the workstation completely, unplug it from the wall, and then carefully reseat the GPIO cable on both the motherboard (TB1 header) and the Thunderbolt card (1BT_GPIO port). Ensure the pins are aligned correctly and the connection is firm.

• Inspect the cable and connectors: Look for any bent pins or damage to the cable or the headers on both the motherboard and the card.

BIOS and Firmware Considerations

Even though you've enabled Thunderbolt in the BIOS, there might be other related settings to check.

• Reset BIOS to Defaults: Sometimes, other BIOS settings can interfere with hardware detection. Consider saving your current BIOS settings, then resetting the BIOS to its factory defaults. After resetting, re-enable only the necessary Thunderbolt settings and see if the card is detected.

• Update BIOS: Ensure your Z8 G4 has the latest BIOS version from the HP support website. A newer BIOS might include improved compatibility and bug fixes for add-in cards.

Hardware Troubleshooting

If the above steps don't yield any results, it's time to consider a potential hardware issue.

• Try a Different PCIe Slot: Although the official documentation specifies PCIe slot 1, it's worth trying another compatible PCIe slot if one is available. This can help rule out a faulty PCIe slot on the motherboard.

• Inspect the Thunderbolt Card: Carefully examine the Thunderbolt card for any visible damage, such as a cracked PCB or damaged components.

Potential Windows 11 Issues

While less likely to be the root cause if the card isn't detected at the BIOS level, Windows 11 can sometimes have driver-related quirks.

• Driver Reinstallation: Uninstall all HP Thunderbolt software and drivers. Reboot the system, and then reinstall the latest drivers from the HP support website. Make sure you are using the correct driver for your specific operating system (Windows 11).

Final Thoughts and Recommendation

Given that you've already performed the majority of the recommended troubleshooting, and the firmware update utility can't even see the card, it does point strongly towards a hardware-level issue. The motherboard is not detecting the card's presence for data transfer.

At this point, it is highly likely that either the Thunderbolt card itself is faulty or, less commonly, there's an issue with the motherboard's PCIe slot or Thunderbolt header.

If your workstation or the Thunderbolt card is still under warranty, I would recommend contacting HP Support directly. Provide them with the detailed list of troubleshooting steps you've already taken. This will help them to quickly diagnose the problem and arrange for a replacement part if necessary.