PC Will Not Boot up When PCIe Card is Inserted

Updated Feb 5, 2021

Reported In


  • PCIe-6374
  • PCIe-1433


Motherboards: ASUS Z270H, Supermicro X11SCZ-Q, HP Z800

Issue Details

  • Why is my PC not booting after inserting my PCIe/PCI card?
  • My PCIe/PCI card worked with my old motherboard then stopped working with my new one. How can I determine if my PC or PCIe/PCI card is causing the issue?


It is important to determine if this issue is caused by the PC, or the PCI/PCIe card. To isolate the issue, you can try the following troubleshooting steps:

1. Determine if the PCIe/PCI card is causing the issue:

  • Re-seat the PCIe Card in the PCIe Slot to see if it is recognized
  • Try the PCIe card in a different PCIe Slot on the same computer to see if it is recognized
  • Try the PCIe card in another computer to determine if the PC or card is the issue. If the card works on another computer see step 2 to check the PC settings as they may differ between computers. 
  • Try a known working PCIe card in the PCIe slot that is having the problem to confirm if the card is the problem
  • Make sure the card is in a compatible slot. For example, the PCIe-1433 is electrically a x4 card. The 1433 supports unplugging, so can be used in x4, x8 and x16 slots.  

2. If the PCIe/PCI card seems to be working correctly, check the PC:

  • Update the firmware/BIOS for the computer motherboard.
  • Disconnect the card to boot the computer and check if all the Windows updates have been applied in Settings >> Windows Update. Some PCs that had this issue, have been able to boot with the card connected after a Windows Update was performed. 
  • Change BIOS settings for the PCIe card from AUTO to GEN1 (Options typically are AUTO/GEN1/GEN2/GEN3). For instructions on how to change your BIOS settings, consult your motherboard's user manual as settings may differ between devices.
  • One of the last resources, if the card is working on other PCs, an image of one of those PCs can be created and installed on the PC that is not booting when the card is connected. This will narrow-down if the cause is at lower level (hardware/motherboard) or can be fixed with a new image of the operating system. 

Additional Information

Some motherboards may not automatically recognize the PCIe Card Version. This will cause the system to try and boot the PC with the PCIe card possibly set to the incorrect version, thus inhibiting the PC from booting up.

ASUS Z270H Motherboard:

In the case of the ASUS Z270H motherboard, it will assume all PCIe cards are V3. However, the version of the PCIe-1433 is V1.1. The PCIe needs to be manually downgraded to fix this. Go into the BIOS of the PC and find the correct setting and ensure it is set to the right version for the PCIe card.

The PCIe-1433 is electrically a x4 card.
For the ASUS Z270H Motherboard, the following slots can be used:
•    PCIe_x16/x8_1 (Electrically a x16 (x8 if PCIe_x8_2 is used)
•    PCIe_x8_2 (Electrically a x8)
Note: Leave the PCIe_x2_3 slot unused.

Supermicro X11SCZ-F/Q Motherboard:

In the case of the Supermicro X11SCZ-F/Q motherboard, the BIOS settings for the PCIe-6374 card default to AUTO. By changing the BIOS setting to GEN1, the PC was able to boot.