if someone buys a cheap back up rig and has a pci card spare or the rig already has a pci card in it then thats cool but if it has a agp slot or a pci ex slot they dont tend to snub the faster slot
people usually have a main rig and sometimes a backup which can be a modern system or an old system the kept or a cheap one they picked up
if you said im getting a CHEAP backup rig for linux or for media or as a pure backup incase your main rig goes we would all be like thats cool but to get a backup rig just to support pci graphics card and one with no agp or pci express slot is stupid, most people look for one thats cheap and then dont get to picky with specs
if i had a card lying around then yes i might use it under certain circumstances but i wouldnt go out of my way to get a pci graphics card
