Installing PCI-E USB card caused massive problems

[eribob]

Hi all wise people! 

Yesterday I installed a PCI-E USB card to pass through to a second VM. The card is this one: https://www.inateck.com/inateck-ktu3fr-4p-usb-3-0-pci-express-karte-mit-4-usb-3-0-ports.html I chose it because the FL 1100 chipset was recommended in another thread here on this forum. 

 

To fit it between my GPU:s I had to use a PCI-E x1 -> x1 riser cable from Kolink (https://www.caseking.de/kolink-pci-e-x1-auf-x1-riser-flachband-kabel-19-cm-grau-blau-zurc-005.html) 

 

The card is recognised by Unraid and shows up in the VFIO-PCI config plugin in its own IOMMU group, however, when I start the server with the card installed it behaves very strange. 

 

The cache drive starts to disconnect and reconnect with the system repeatedly, resulting in it being registered as an unassigned device, and when I try to update my VM xml I get an error message saying that the disk has entered a "read only state". I also get warnings that my cache drive is unreachable. Further another SSD that I pass through to a VM using "/dev/disk/by-it/[DRIVE ID]" is suddenly not found. 

 

Also during startup, instead of endning with the login command line prompt and the server IP address as usual, I get the following screen: 

 

It never goes further, but the server is eventually reachable over the network as usual anyway. 

 

My initial thought is that this could be a power issue, that my Corsair 750W PSU is stretched thin (i have a ryzen 3950X, 64GB DDR4, Rx580, R7 370, 4HDDs, 3 SSDs and 2 NVME drives, as well as some case fans). Do you agree or is there another possible explanation? 

 

Against this power theory, the problem occurs even though the system is not under any substantial load however. In addition, I tried to remove the SATA power cable from the USB card, but left the PCI-E connection inserted and the problem persisted. It did not go away until I disconnected the card from the PCI-E port. 

 

Another theory is that maybe my motherboard shares PCI lanes between some of the SATA ports and the PCI-E x1 port that I want to use for the USB card. I have an asrock taichi x570 board. 

 

I forgot to save the diagnostics! I can re-insert the card and recreate the error if diagnostics would be helpful though. 

 

Thanks for support in advance!