PCIe slots are a type of expansion card slot found on personal computers. They are often used to install additional devices, such as video capture cards or sound cards.
There are different types of PCIe slots, but all of them use a common communication protocol. This means that PCIe cards can work with other PCIe cards and devices, as well as with regular USB ports.
Some people think that capture cards use PCIe slots because they offer more bandwidth than regular USB ports. However, this is not always the case.
Some capture cards use regular USB ports instead of PCIe slots because they don’t offer enough bandwidth for what the card needs.