An alternative to modifying the video card is to notch the back of the pcie x1 slot so that the pcie x16 card can plug into it. Both slots accept usb 30 cards and can be used to add usb 30 ports.
You have to make sure there is clear. There are two types of expansion slots on computers pci and pci express pcie. Pci express devices communicate via a logical connection called an interconnect or link.
Delock 4x Serial Pcie X1 62922 Starting From 49 15 2019
A link is a point to point communication channel between two pci express.