PCIe x1 Gen2 Host - PCIe Cable Adapter

Intel no longer supports PCIe x1 controller cards plugged into PCIe x16 slots starting from the Alder Lake desktop PCs, which are HP G9 platforms

Therefore, users can insert a card using PCIe x1 interface into a PCIe x4, x8 or x16 slots when the PCIe x1 slot has been occupied, which solves the problem of

pcie 40 in 30 slot Or will they only work on a PCI-Ex1 slot? Reason being I am looking at buying an MSI 990FXA-GD80 MoBo I want to use the second card slot

pcie 40 in pcie 30 slot Yes, a x1 card should work in a x16 slot It's good that you've got it to work in a x1 slot What else have you tried it in besides the x16 slot