Pcie slot instability?

Hi,

I want to extend the storage by adding a pcie gen 4 x4 to dual nvme adapter but I’m not sure which is fine to use since there are som reports of such devices not working. Some examples:

Any ideas are welcome, I would love to add some more storage!

This seems like the same issue I’ve been having with a dGPU on the PCIe x4 slot:

Edit: Found this one too?