I'm always a little confused when folk write they will use that because they paid for it when a free small app that works very well for most of us does the capture step without too much fuss (actually no fuss at all for me.)
I have never found any PCIe card to work in a PCI slot or vice versa. I get the card for the slot but moving to PCIe does move part of the connection up a notch so why not? It certainly has not been an issue for over a decade but if you got the slot, use it.
I didn't write the Pinnacle was _rappy but that I found it easier to use a capture app for capture and an editor for editing.