BIOS message after installing PCI Express x4 card: Detection error 43A-USB Type-C 12C not connected.

[EricN-Tech]

Make/Model: StarTech.com PEXUSB312EIC

Description: 5-Port USB 3.1 PCIe Card - 1x USB-C (10Gbps), 2x USB-A (5Gbps) + 1x 2-Port IDC (5Gbps)

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Error: After installing the card, End-User gets the following error message during POST: "USB Type-C card detection error 43A-USB Type-C 12C not connected."

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According to page 63 of the HP Manual: Computer is expecting an HP-specific Type-C/I2C sideband connection.
Source: https://h10032.www1.hp.com/ctg/Manual/c06099795.pdf
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Issue: The StarTech.com PEXUSB312EIC card does not use/need that connection.
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Troubleshooting:

- Card has been properly installed.

- 15-pin SATA power connector has been connected.

- StarTech.com driver has been installed.

- HP BIOS has been updated to the latest version available.

- No matter how many times the computer is reboot, the same POST error shows up. It can be bypassed and the card works fine, but it's slightly inconvenient.

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Is there a way to disable this message in the BIOS? Any Advice is appreciated!

[Pallipurath · Accepted solution]

Hi @EricN-Tech 

Welcome to the HP Support Community.

Thank you for posting your query.

Since the card is functional and the error is generated by the HP BIOS during POST, the resolution depends on whether you want to eliminate the message or simply verify that the system is operating correctly. I would request you to pelase refer the Maintence Guide. Meanwhile I would request you to perform the below steps.

Verify the PCIe Card Installation

1. Shut down the computer.
2. Disconnect the power cord.
3. Remove and reseat the StarTech PCIe card.
4. Verify the card is fully inserted into the PCIe x4/x16 slot.
5. Ensure the SATA power connector is firmly attached to the card.
6. Start the system and check whether the message persists.

Update the BIOS

You have already completed this step, but for completeness:

1. Install the latest BIOS available for the HP system.
2. Restore BIOS defaults after the update.
3. Reboot and test.

The message may still appear because the issue is related to hardware detection logic in the BIOS rather than a BIOS defect.

Check for an I2C Header on the Expansion Card

HP documents Error 43A as: Cable is required between I2C on card and USB-C on the system board.

Inspect the expansion card:

• If it includes an I2C header, connect it according to the workstation's service guide.
• If there is no I2C header (which is the case with many third-party USB-C cards), the HP requirement cannot be met.

Verify Whether the Card Is HP-Certified

The BIOS is designed around HP-supported Type-C expansion cards that provide additional management communication through I2C. A third-party card such as the StarTech PEXUSB312EIC may not support this interface and therefore triggers the warning.

Take care and have an amazing day!

[EricN-Tech]

Thank you for your reply Pallipurath. I believe there's an option to suppress POST errors. I will give that a try.

[Pallipurath]

Hi @EricN-Tech 

Thank you for responding.

I understand that you are receiving the BIOS error 43A related to the USB Type-C controller after installing a PCIe x4 expansion card. If your system BIOS provides an option to suppress or ignore POST errors, you may certainly try that and check whether the system boots normally afterward.

However, I would recommend confirming that the PCIe card is fully compatible with your HP system and that it is properly seated in the slot, as the error may indicate a hardware detection or initialization issue rather than a BIOS fault. After enabling the POST error suppression setting, please let us know whether the system operates normally and whether all functions of the newly installed PCIe card are working as expected.

Have a good day