PCIe USB Expansion Card Breaks Ethernet (Linux)

Gerowen · May 16, 2023

Debian stable (bullseye). Older hardware; an Alvorix motherboard and an AMD Phenom II x6 1045t CPU. System is acting as a home server/NAS and is headless; no GUI installed. The on-board ethernet is only 100Mbps, so some years ago I installed a PCIeX1 gigabit card. I also just installed a PCIeX1 SATA expansion card. I recently purchased a PCIeX4 USB card to give me 4 USB 3.2 type A ports and 3 USB type C ports. The motherboard did not have any available x4 slots, so I put the card in the one x16 slot that the motherboard had. Upon doing this, the system booted fine, but would not give power to the gigabit ethernet card and didn't show it as even existing with "sudo ip address", and the on-board ethernet would not activate or pull an IP address.

Could this be an issue with running out of PCIe lanes? Could the USB card be drawing too much power? Is it an issue with firmware/drivers for the card? Removing the USB expansion card fixed the issue. It would be nice to have the higher speed USB ports for updating my off-site backup drives once a month, since the on-board ports are only USB 2.0. I'm just not sure where to begin troubleshooting.

For reference, this is the card I purchased.

https://www.amazon.com/dp/B09ZKNJDNW?psc=1

BiotechBen · May 16, 2023

35 minutes ago, Gerowen said:

Debian stable (bullseye). Older hardware; an Alvorix motherboard and an AMD Phenom II x6 1045t CPU. System is acting as a home server/NAS and is headless; no GUI installed. The on-board ethernet is only 100Mbps, so some years ago I installed a PCIeX1 gigabit card. I also just installed a PCIeX1 SATA expansion card. I recently purchased a PCIeX4 USB card to give me 4 USB 3.2 type A ports and 3 USB type C ports. The motherboard did not have any available x4 slots, so I put the card in the one x16 slot that the motherboard had. Upon doing this, the system booted fine, but would not give power to the gigabit ethernet card and didn't show it as even existing with "sudo ip address", and the on-board ethernet would not activate or pull an IP address.

Could this be an issue with running out of PCIe lanes? Could the USB card be drawing too much power? Is it an issue with firmware/drivers for the card? Removing the USB expansion card fixed the issue. It would be nice to have the higher speed USB ports for updating my off-site backup drives once a month, since the on-board ports are only USB 2.0. I'm just not sure where to begin troubleshooting.

For reference, this is the card I purchased.

https://www.amazon.com/dp/B09ZKNJDNW?psc=1

Have you considered going into BIOS to see if there are PCIE configuration settings such as 16x4, 8x8x4, and 4x4x4x4? Sounds like lane allocation is not happening correctly.

Gerowen · May 23, 2023

On 5/15/2023 at 10:34 PM, BiotechBen said:

Have you considered going into BIOS to see if there are PCIE configuration settings such as 16x4, 8x8x4, and 4x4x4x4? Sounds like lane allocation is not happening correctly.

I'll check and see if there are options in there to change regarding that. Not sure it would have them since it's not a server board, but it doesn't hurt to look. Thanks for the suggestion,

BiotechBen · May 23, 2023

3 hours ago, Gerowen said:

I'll check and see if there are options in there to change regarding that. Not sure it would have them since it's not a server board, but it doesn't hurt to look. Thanks for the suggestion,

I only say that because I had issues with PCIE lane config on my b450 ASRock board and going through those settings and configuring them correctly was what fixed it.