[Coda]

It's not a problem in that sense. Some laptops actually do have a place for it for it; it's just rare. Slightly less rare is for a laptop to have a high-speed boot drive that's kinda low capacity and then a larger drive for storage. And if it's actually an upgraded drive instead of a secondary drive then that's not a problem at all as long as Windows got reinstalled correctly.

I just spoke a bit hastily and didn't communicate it well -- if there's not a way to install one at all, then trying to install one is going to be a super invasive process, and that is of course going to be a problem. But you'd KNOW if that was the case, because there would probably be holes cut in the body or something. I've only seen it done a couple times and that was by people who make a habit of doing crazy mods to stuff.